What makes us who we are: Behavioral Genetics and Socialization by Parents and Other

Agents of Socialization

Parents show an intense desire to influence the kind of people their children will grow up to be. This intense desire created a demand for expert advice that the young discipline of Psychology supplied from the beginning and continues to supply today. The special kind of responsibility that parents take and are expected to take for the people their children end up becoming is the obvious source of this intense desire. We don’t blame anyone else for another person’s shortcomings the way we blame a parent for those of their child. Many parents experience the daily reality of trying to parent as a struggle to retain some measure of control over the kind of people their children are becoming based on this peculiar responsibility. You can’t take that much responsibility for who another person is going to turn out to be without wanting to control the ongoing process that makes that person who he or she will finally become without acting like what would be called a control freak in any other context. In a parent, this controlling behavior is simply a matter of trying to guide and control a process—the process involved in becoming a particular kind of person—knowing full well that you will be held responsible, for better or worse, for whatever the final result of that process turns out to be. Most parents want to believe that they have a great deal of influence over the kind of adult their children will become. Popular culture in general and Pop Psychology in particular encourage them to think they do and even tells them exactly how they can exercise this vast influence effectively.

With one notorious exception, no one has ever claimed with a straight face that parents have no significant direct influence, but many reputable scholars, including a consensus of researchers in the field of Behavioral Genetics, now question if they have as much influence as they are commonly believed to exercise or even enough influence to justify the degree of guilt by association a parent incurs if their child does something truly awful or simply cannot cope with the demands of life as an adult. We may be assigning more guilt than actual blame would justify when we encourage parents to ask where they went wrong whenever a child crashes and burns in spectacular manner.

Francis Galton, Darwin’s cousin, first coined the phrase nature and nurture to refer to heredity and environment (Harris & Pinker, 2011) and it has become a catchphrase. Galton was a convinced hereditarian of the “blood will tell” Victorian snob variety who would have been fascinated by the results of modern-day behavioral genetics research. Using nurture for the opposite of nature, by which Galton clearly meant what he called heredity and we today call the genetic contribution, introduced a bit of wiggle into things that later helped researchers claim anything that was not directly attributable to genetics to the influence of parenting. Early socialization researchers often attributed any similarity between parents and their children to the influence of parents as agents of socialization; parents were routinely seen as the primary agents of socialization and held almost exclusively responsible for passing down civilization as they had known it to the next generation. This was a heavy burden to bear. It is easy to see why generations of parents whose enculturation strongly encouraged them to believe that they individually held the fate of their children in their hands, while parents collectively held nothing less than the fate of civilization, felt that parents needed all the expert help and advice they could get, and maybe then some.   At this same time, the old style snob hereditarians like Galton were numerous enough and sure enough that “blood will tell” to give Edgar Rice Burroughs’ stories about the enfant Lord Greystroke, AKA Tarzan, an ideological sub-text that is lost on most modern readers; it was not just anyone who grew up to be the lord of the apes and king of the jungle after being raised by apes but someone with the blood of an English aristocrat.  So, the earliest hereditarians attributed whatever truth there was in the old saying “ like father like son” to the idea that “blood will tell,” whereas the earliest environmentalists were just as happy to claim this same similarity as the fruit of a primary socialization process most of them naively assumed took place almost exclusively in the home (Condit, Ofulue, & Sheedy, 1998).

Although the catch-phrase nature versus nurture is still widely used in the popular press and by the general public, contemporary developmentalists, regardless of theoretical orientation, carefully avoid this dichotomy in order to distance themselves from all the baggage left over from the Victorian era controversies briefly reviewed above. A more accurate description of what this long-term dispute has morphed into in our time might be behavioral genetics versus socialization. Even contemporary developmentalists who are more interested in socialization do not assume that the home is the only place socialization takes place. Group Socialization Theory, for example, looks closely at the role of the peer group as an agent of socialization. Researchers looking at primary socialization in the family of origin now put forth theories based on interaction effects among genetics, parenting and, sometimes, other agents of socialization. Behavioral geneticists do the same. The field of developmental psychology is currently dominated by people who see the question of how we become the people we are as adults as being too complex to have a simple answer; they cringe at questions stated in terms of nature versus nurture because the answers provided by the best research done so far will not fit into that neat dichotomy.  My long and somewhat awkward title reflects the necessarily complex and nuanced nature of any answer to this question that could be taken seriously by any reputable developmentalist given what the full range of solid research in the field makes it safe to say at present.

Some researchers have minimized the importance of the role of parents and their influence on a child’s personality while still focusing on socialization more broadly defined. In her article “Where is the Child’s Environment? A Group Socialization Theory of Development,” Judith R. Harris proposes the Group Socialization Theory (Harris, 1995). Harris’ theory, while acknowledging the contribution of genetics, primarily highlights the importance of peer groups as agents of socialization. In so doing, it simultaneously discounts the significance of parenting, going so far as to say that parental influence may sometimes be statistically significant in fairly large samples but is finally of little if any practical significance. This bold claim that parents finally don’t matter much generated a large amount of controversy and criticism among child development specialists and was not accepted by experts.  It is not Group Socialization Theory per se that was rejected unanimously and emphatically by the experts. The importance of peer groups is now commonly acknowledged in the field; what has been rejected is the idea that parents do not matter. The topic of the entire of Chapter 13 of Social and Personality Development by David R. Shaffer (2008), the textbook used last term at this university in Psychology 527–Lifespan Personality Development, is the influence of peer groups as agents of socialization. Chapter 14 looks at the Internet and other media as agents of socialization. At present, developmental researchers typically work more in behavioral genetics than socialization or vice versa, but researchers who concentrate on one acknowledge the importance of the other. With the exception of Harris, no one flatly denies the importance of parents as agents of socialization while practically everyone acknowledges that parents, even if they are the most important agents of socialization, a claim most would still support, are not the only important agents of socialization; further, parents exert some of their influence not directly but through interaction effects involving genetics and/or some other agency of socialization. As mentioned earlier, no one with any present standing as a developmentalist really believes that the answer to the question of how and why we become who we are as adults is simple.

Earlier theories of what factors are responsible for adult psychopathy and normal behavior were numerous and varied. Perhaps the most well-known is that of Sigmund Freud.  Freud theorized that emotional disturbances were the result of repressed fears and desires in the unconscious mind. Freud taught that primary socialization within the family of origin creates both the normal adult personality and all the various psychopathologies to be observed in the adult population. Bathroom graffiti such as “My mother made me a homosexual; if I give her the yarn, can she make me one too?” show how widely Freud’s influence still extends in popular culture. Many of Freud’s ideas have now been rejected but his assumption that adult personality and especially the emotional problems of adults have their etiology in the psychodynamics of the nuclear family is still potent. This notion alone is enough to keep many parents more fearful and insecure that their good intentions and common sense are enough to make them good enough parents not to outright damage their children for life than they would be otherwise. It also makes them much more likely to think that they must have done something wrong if an adult child goes wrong in any of the thousand ways (drug addiction, criminality, lack of career success, etc.) that human beings do go wrong. Freud still has influence in spite of the fact that his theory of personality development through primary socialization within the nuclear family is no longer accepted without qualification by practically anyone because almost every major researcher since Freud who has focused on parenting as a primary socialization process shaping adult personality has borrowed something important from Freud.

John Bowlby, the British psychologist and psychoanalyst who was the first researcher to think in terms of Attachment Theory, would be one example (Bowlby, 1969). Bowlby’s hypothesis that a child must have a primary caregiver who is responsive and available in order for the child to develop a sense of security is neither an idea explicitly put forward by Freud nor, in any direct sense, the further development of a Freudian doctrine. However, I would still claim that Attachment Theory could only have occurred to someone after a way of thinking about the relationship between the psychodynamic of the nuclear family and whatever subsequent problems in living the adult child might later experience ceased to be novel. This way of thinking might have seemed far-fetched to many people when Freud first put it forth but later became widely known and widely enough accepted to make an argument that presupposed this relationship read like something other than crack-pot gibberish. Freud created a climate of thought that made Attachment Theory thinkable and, for some, plausible. Originally Bowlby was heavily criticized and essentially ostracized from the scientific community.  Yet, to this day, Attachment Theory is still respectable enough among developmentalists to provide a source for hypothesizes worth testing, especially in the context of divorce and child custody (Main, Hesse, & Hesse, 2011).  Baumrind's work on parenting styles is another example of work that takes place within a horizon of possibility created by Freud considered as a cultural influence shaping the climate of thought without being, in any strict sense, so based in Freud that rejecting Freud would also require throwing out Baumrind. Both Bowlby’s work and Baumrind’s work is old enough to be somewhat out of date per se but not so out of date that you would not find both Bowlby and Baumrind in the references section of many recent publications. I do not have access to the Social Science Citation Index to check this, but I would be surprised to not find one or both of these names cited by many recent publications. If I were surprised, I would check the references of recent research and argue from the frequent presence of my two names there that the work of Baumrind and Bowlby is now seminal to current research on the influence of parenting on adult personality.

In 1943, psychologist Leo Kanner coined the phrase refrigerator mothers when he posited that children became autistic because their mothers lacked the maternal warmth needed for healthy development.  Bruno Bettelheim picked up this idea of refrigerator moms and it remained the conventional wisdom of the English speaking world throughout the 1950s and 1960s.  According to the touching and beautiful documentary film directed by renowned actress Sandrine Bonnaire telling the story of her autistic sister, Sabine, this kind of thinking was, in 2007, still widely accepted enough in France to justify “therapy” that ignored the genetic basis of autism all together and would plainly be interpreted as torture by anyone shown the film of what was being done to Sabine without any explanation of why it was being done (Kartemquin Films, 2003). The contrast between Sabine in her teens, as revealed in home movies edited into the documentary by her sister, and the heartbreakingly less functional and less joyful person she had become after years of institutional “therapy” makes one sad, angry and frustrated in response to the intense sadness, flashes of free-floating anger and utter helpless frustration that had become a routine part of her typical day thanks to all that “professional help.”

My intention in presenting material about the refrigerator moms is to recount the worst example of the harm done to everyone involved when parental influence is grossly overestimated. The story of autism and the refrigerator moms is the most disturbing example of this kind of mistake because mothers who gave birth to babies who were behaviorally different in ways so pervasive and striking that the difference is now listed in the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 2000, 4th ed., text rev.) as a family of pervasive developmental disorders grouped together as the Autistic Spectrum Disorders (ASD) were told that this difference was something they had done to their child by being refrigerator moms rather than the loving and emotionally available caregivers moms normally are. This was wrong both factually and morally. The behavioral symptoms of autism are now recognized as a birth defect as much as the missing or stunted limbs of thalidomide babies. One huge advantage to giving birth to an armless thalidomide baby over giving birth to a severely autistic child during this same period of time is that no one ever tried to tell the mother of that armless baby that those limbs would sprout right out eventually if she just responded to her baby the way normal moms naturally do. Refrigerator moms become refrigerator moms because of the heartbreakingly atypical way their children react to them and not the other way around. Their behavior is more accurately described as expressing the grief and despair of a mother defeated in her natural craving to bond with her child by responses that range from indifference to distress. One can imagine how being blamed for the pervasive difference between the way this child is developing and the way most children do would rub salt into that wound.

ASD has now been the subject of investigation for decades. Although there is no single cause of ASD, researchers are starting to identify specific genes that may increase the risk for ASD and have discovered that if one identical twin has ASD, there is a nine out of ten chance that the other twin will have it as well.  Siblings of a child with ASD have 35 times the normal risk of developing the disorder (Arking et al., 2008).

The Autism Phenome Project at UC Davis's M.I.N.D. Institute is currently in the process of separating out different autistic phenotypes in their study investigating 1,800 children with autism.  It is a longitudinal study that, among other things, hopes to determine which genes are involved in children diagnosed with autism (UC Davis Mind Institute, 2006). 

In addition, the lack of both a theory of mind (Baron-Cohen, 1990) and empathy found in ASD is now linked to a very specific set of differences in brain structure consistently found to separate persons on the autistic spectrum from neurotypicals (Elsevier, 2011).  The refrigerator mom example is important to many as the most disturbing instance in which our cultural tendency, inherited from Freud, to search for the etiology of the emotional/behavioral problems of present and former children, that is to say absolutely everyone living or dead, in the psychodynamic of the family of origin lead us to blame bad parenting for what a more advanced knowledge of neuroscience and behavioral genetics now lets us see clearly as a birth defect. This was a false attribution based on cultural defaults of interpretation that made one interpretation more plausible than any other in a situation where no one actually knew enough about ASD to make more than a guess about etiology. These cultural defaults of interpretation lead us to blame parents for an atypical developmental pattern that significantly limited everyone who clearly showed that pattern, many so severely that independent living would never be possible, because our knowledge of neuroscience and behavioral genetics was not sophisticated enough at that time to allow us to find the true etiology of ASD there. Every culture has such interpretive defaults and every culture scape-goats on the basis of these defaults, sometimes with results far more gruesome than what I am describing here—the interpretive default that led medieval Christians, when the plague came, to assume that Jews had poisoned the wells was more deeply hateful and did more harm. But, both events are an example of exactly the same process at work. The other examples I will discuss are less shocking, less extreme but still significant as further examples of the way advances in behavioral genetics and other sources of new information have provided solid evidence that we both blame parents and encourage parents to blame themselves far more for some outcomes than is appropriate, given their real ability to prevent such outcomes even by exerting all the influence they actually had with all possible wisdom.

The advance of behavioral genetics has made it possible to explain much of the variance in nearly all of the variables that socialization, either within the family or more broadly defined,  has been put forward to explain previously by appeal to the degree of kinship between individuals alone. Behavioral geneticists conduct twin studies and other studies of related persons to get a reliable measure of how much of the variation in a given characteristic is determined by genetics. Identical twins are important to this research, especially identical twins who were raised apart. Each pair of such twins is identical genetically but the environment they experienced will be similar only to a degree determined by random chance (Plomin, Fulker, Corley, & Defries, 1997).

If such pairs of separated twins are alike on personality variables, intelligence or even in the kinds of recreational activities they enjoy, that similarity is evidence of a genetic component in determining those characteristics (Plomin & Daniels, 1987). Identical twins raised separately have been found to be very similar on intelligence and a wide range of personality variables including loneliness (Boomsma, Willemsen, Dolan, Hawkley, & Cacioppo, 2005) and personality disorders  (Kendler, Myers, Torgersen, Neale, & Reichborn-Kjennerud, 2007) just to select two at random from a long list. Fraternal twins and siblings are also similar on all these variables to a degree that is typically less than that found in identical twins to roughly the same degree that their genetic similarity is less than the perfect match found in identical twins.

The problem this creates for socialization researchers is that behavioral genetics can explain similarity between parents and children or between siblings on most of the dependent variables that socialization researchers have previously thought to explain using agents of socialization as the independent variable by appeal to degree of shared genetics as independent variable. There is only so much similarity between parents and children or between siblings on any given variable to be explained. The more of the total variance that can be explained strictly by appeal to the direct effect of genetics, the less variance is left over to be explained by any one agency of socialization, for example, by parental influence or by all agencies of socialization combined. Often, if we take the correlation between degree of kinship and variance on a characteristic at face value as a direct effect of genetics, there is not much left for socialization to explain. If we further assume that all the remaining variance is explained by socialization but that most socialization does not take the form of direct parental influence, Harris’ idea that parents don’t matter much starts to make sense. Most developmentalists rejected this idea by taking all correlations between degree of kinship and variance on any important personality variable as measuring not just the direct effects of genetics but also the interaction effects of genetics with anything else that mattered distorted by failure to correct for the correlation between genetics and what else actually mattered. These alternative assumptions almost surely map reality more accurately and, when fleshed out as a theory that can generate a model that actual data can either fit or not, will almost certainly need a direct effect of parental influence plus some interaction effects involving parental influence to fit well. However, this direct effect will almost certainly not be nearly strong enough to justify blaming parents for the inadequacies of their adult children to nearly the extent that we presently do. When we look at adult adoptees, the results are not promising for socialization factors as strong independent variables even after correction based on alternative assumptions and a more complex model as described above. The correlations on IQ and personality variables in adulthood for unrelated children adopted into the same home are usually near zero (Plomin & Daniels, 1987). Consistently, the correlations on such variables are higher for siblings raised apart than for unrelated adoptees raised together (Plomin, Chipuer, & Neiderhiser, 1994). The finding that identical twins raised together are no more similar on these same variables than identical twins raised apart is also daunting for anyone trying to rescue socialization in whatever form as a strong independent variable (Plomin, Fulker, Corley, & DeFries, 1997).

Recent studies on intelligence have found that when comparing identical twins raised apart, fraternal twins raised apart, and adoptive siblings, there is a high correlation between degree of kinship and IQ (.86; Plomin et al., 2003).  A later study focusing on high cognitive abilities (people within the top 1% of general intellectual ability) concluded that the genetic influence was considerable, whereas shared environmental influences were moderate (Haworth et al., 2009).

A 2011 study conducted at the University of Edinburg looked at the DNA of 3,511 unrelated adults and found that 51% of the variation in problem-solving skills and 40% of the variation in knowledge could be accounted for by the differences in DNA (Davies et al., 2011).

One of my favorite stories, the one I will tell occasionally at social gatherings for years to come involves a pair of identical twins reared apart that was part of the huge twin study conducted at the University of Minnesota. Both had been raised by dour parents who expressed little emotion. They became known as “the giggle twins” because both said that she had never met anyone else who giggled as much as she did until she met her twin (Lykken et al., 1992). I like to think of them as laughing at the sheer hubris of over-bearing control-freak parents everywhere; contrary to what J. B. Watson believed and such parents would like to believe, newborns do not come out of the womb as blank slates just waiting to be inscribed with whatever living memorial or message to the future such parents would like to leave behind. Newborns come into this world with a temperament; for purposes of the current discussion, I am using “temperament” to mean whatever part of personality is genetic. I might say that a new-born came into this world with a strong genotype pull in favor of being cheerful as opposed to gloomy or lazy as opposed to energetic. However, if I did, I would not mean that the child was either doomed at birth to sloth or blessed at birth with a sunny outlook. But, I would mean that parents who insisted on trying to make that particular child grow up hard-working but gloomy in the style of those Norwegian bachelor farmers Garrison Keillor loves to poke fun at are assigning themselves a task that, while not as strictly impossible as teaching a pig to sing, will prove only slightly less frustrating. I would also think that, if they succeeded, the result would be something like a human bonsai tree. I find it hard to believe that the final phenotype that would result from this process of twisting and channeling development against the grain of the genotype would be a happy, well-adjusted person.

Freud wanted to be a novelist. He only became a medical doctor because his parents insisted. Freud later went on to create a form of medical practice perfectly suited to a Jewish doctor who could not stand the sight of blood but loved listening to his patients talk about their childhoods and the neurotic agonies that plagued them at present. Freud then played Sherlock Holmes in relation to this material and usually solved the case by discovering that either mom or dad or both together did it. Freud justified his new “science” by appeal to “clinical case studies” that read like detective thrillers worthy of Arthur Conan Doyle or Agatha Christie. Many German scholars who cannot take Freud any more seriously as a scientist than they take Anton Mesmer none-the-less acknowledge him as one of the great prose stylists of their language. When I teach World Literature II, I assign an English translation of Dora; perhaps the “case study” that has been mostly thoroughly debunked as such, because it is great literature even in translation. The most vital part of Freud’s legacy today is our tendency to assume or, at very least, strongly suspect when confronted with a monster such as John Wayne Gacy or Jeffery Dahmer, that their parents must have done something really awful to a child born not much different than most children. Freud’s idea that being twisted into unnatural shapes by mom and dad during childhood explains much of the discontent later experienced in adult life is probably true of Freud, me, and many people who were born into this world with a genotype that ran strongly against the grain of what their parents were determined to produce. I think that such persons are a minority in the general population but, perhaps, not in the population of clients who sought out Freud’s couch or the help of those who today offer some version of the talking cure.

The approach to parenting that based on what we know at present seems to actually work best would fit with this version of how to either raise a well-adjusted adult or twist the child in ways that will cripple the adult. The authoritative parent (Baumrind, 1966) is flexible in ways that would make it possible to adjust parenting to go with the grain of the genotype and, also, to either mitigate the damage done or reinforce the benefits offered by the other agents of socialization important to the child’s development. This means letting go of unreasonable expectations that run counter to the person the child is becoming. This will sometimes mean nothing more painful than accepting that, whereas a daughter may be as beautiful as her mom was at 18, her natural shyness means that she should never be given the impression that she will let her parents down by not following in mom’s footsteps as homecoming queen. If you are Momma Clinton, it may mean accepting that Roger, in spite of everything you can do, will probably not make it through college but might manage, with a little luck, to stay out of prison whereas Bill might end up, with that same little bit of luck, as Governor of  Arkansas or even President. The authoritative parent would be realistically aware of who each son was becoming and of the limits of what a parent can do to help in each case without withdrawing love and concern from either son.

The earliest research into the origins of criminal behavior focused on physical characteristics.  In 1876, Cesare Lombroso concluded that people who commit crimes have atavistic features such as receding foreheads and protruding jaws. This notion, of course, has been long discredited.  Most of the subsequent research into criminal behavior has focused on environmental and social factors, including the role of parental influence and style of parenting.  Recent studies have indicated that although there is no crime gene, certain individuals are born with a genetic predisposition to antisocial behavior. Having this predisposition does not mean a person will grow up to be a criminal; it simply means that some individuals are more likely to engage in criminal behavior when other factors, such as low socioeconomic status, are present and may even turn to crime in spite of socialization factors that one would expect to push hard in the opposite direction. In 1984, researchers conducted an extensive study using 14, 427 Danish adoptees (Mednick, Gabrielli, & Hutchins, 1984). Participants included adoptees and both their biological and adoptive parents. For the present purpose, the most interesting way to look at these adoptees is to look at them as having been sorted into four groups by random assignment and then comparing rates across groups, the rates being the rates of criminal activity in each group. The highest rate of criminality for male adoptees was found among the group with criminal biological parents and criminal adaptive parents. In the group in which both genetics and socialization can be seen as pushing in the direction of criminality, 24.5 % of male adoptees were criminals. In this group and every other, the rate for females was lower but the hierarchy of risk among groups was the same. In the group in which adoptees were most at-risk, roughly three in four male adoptees resisted the push toward criminality. Twenty percent of male adoptees had convictions if their adopted parents did not but their biological parents did. 14.7% of male adoptees had convictions if their adopted parents did but their biological parents did not. If neither the adoptive nor the biological parents had been convicted, 13.5 of adoptive sons had convictions in spite of being part of the group least at-risk. Roughly one in four were criminals in the most at-risk group while roughly one in seven were criminals in the least at-risk group. If we accept convicted biological parents as a valid operationalization of criminal genetics and convicted adoptive parents as a valid operationalization of criminal socialization, we could claim that genetics is more important as an independent variable determining criminality than socialization. But how much does this mean when both together make only the difference between 24.5 among those most at-risk and 13.5 among those least at-risk? I don’t see this difference as enough difference to reflexively blame parents if their children grow up to be criminals or to take criminals seriously who present themselves as victims of who their parents were and of where and how they were raised.

Is a child raised by same-sex parents more likely to become gay? This topic has generated a heated debate that has lasted many years and is still a passionate bone of contention among Americans today. In 1992, Vice-President Dan Quayle declared that homosexuality "is more of a choice than a biological situation.... It is a wrong choice" (De Witt, 1992). Fewer and fewer Americans agree whole-heartedly with Quayle’s condemnation of homosexuality but the debate over whether same-sex attraction is as biologically determined as eye color or as much a choice as Dr. Pepper as opposed to Pepsi or somewhere in between still rages on. The narrower question of whether children raised by same-sex couples are more likely to be gay or lesbian is now empirically settled as a result of the large population and ever-growing population of adolescents and young adults raised by same-sex couples who are now available to provide representative samples for study. Such studies consistently show that children raised by same-sex couples are no more likely to be gay or lesbian than children raised by opposite-sex couples; it turns out that your mother cannot make you a homosexual even if she is a lesbian and her partner is too. Given that sexual orientation is a very basic dimension of personality and highly resistant to change once established, the finding that opposite-sex couples are neither significantly more nor significantly less likely to produce gay or lesbian offspring argues that opposite-sex couples who wanted heterosexual offspring but raised homosexual offspring instead should not spend too much time worrying about where they went wrong as agents of socialization. The truth really does seem to be that parental socialization matters so little in determining this particular personality variable that nothing that they did either pushed or pulled in either direction enough to matter (Bailey, Bobrow, Wolfe, & Mikach, 1995; Golombok & Tasker, 1996; Gottman, 1989).

The list of important personality variables in which parental socialization can plausibly be argued not to matter much is still too short to justify Harris’ broader dismissal of parental socialization in general. The list of such variables in which the argument that the direct influence of parenting is much weaker than once thought is much longer but shortens again when we take into account not just the direct influence of parenting but all the interaction effects that involve parenting. Even after refining our models in this way, we must admit that, although the influence of parenting on the adults that we become is more than practically important enough to justify parenting as a core research topic in developmental psychology, parents, for better or worse, are not as powerful as they were once thought to be. This is good news in the sense that, if we tell parents that their ability to shape the people that their offspring will grow up to be is significant but, in most cases, not anywhere close to determinate, we can also tell them not to feel so guilty when their adult offspring go deep into debt or get busted for DUI or screw up in another of the many ways that an adult can screw up his or her life. We can also tell them that, if they avoid both obvious neglect and abuse either physical or psychological, they will almost certainly not harm their children beyond repair through whatever less than perfectly wise parenting decision they might make over the years.

References

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