Parents may not favor sons or daughters overall, but they appear to invest in them differently across specific areas of childhood, according to new research. The study, titled Sex Biases in Patterns of Parental Investment and published in Human Nature, suggests that the type of support children receive often varies depending on both the parent’s and the child’s sex, revealing a more nuanced picture of parenting than previous research has suggested.
Rather than showing simple favoritism toward sons or daughters, the findings suggest that the kinds of support children receive may be just as important as the overall amount of parental investment. Mothers and fathers appear to contribute in different ways, while sons and daughters receive different forms of guidance, encouragement, and support instead of unequal amounts of care overall.
How the Study Was Conducted
The study was led by University of Texas at Austin doctoral researcher F. Sid Dougan, who analyzed data from 105 adults participating in a long-term study of newlywed heterosexual couples. The participants had originally been recruited in 1989 through marriage records in Washtenaw County, Michigan.
At the time of the survey analyzed in this study, participants were between 19 and 36 years old, with an average age of 26. Most identified as White and had grown up in suburban communities in the United States, meaning the sample reflected a Western, educated, industrialized, rich, and democratic (WEIRD) population.
Participants completed a 105-item questionnaire describing how their biological mothers and fathers behaved during their childhood. Each behavior was rated on a scale ranging from 0 (“not at all”) to 7 (“a great deal”), allowing researchers to compare different forms of parental investment.
Measuring 13 Different Types of Parenting
To improve the questionnaire, the researchers removed items that overlapped or lacked specificity. The final version measured 73 parenting behaviors grouped into 13 domains designed to capture the wide range of ways parents invest in their children.
These included direct care and domestic support, bonding and emotional support, social and moral guidance, education and career support, discipline and regulation, protection, material provisioning, wisdom and life guidance, mating and relationship guidance, athletics and physical training, mechanical and practical skills, competitive encouragement, and sexual permissiveness.
The researchers interpreted these patterns through the lens of evolutionary psychology, which proposes that mothers and fathers may have developed different parenting strengths and that sons and daughters historically faced different adaptive challenges requiring different forms of parental support.
Mothers and Fathers Contributed in Different Ways
When all parenting domains were considered together, mothers reported investing more overall than fathers, particularly in daughters. However, examining individual parenting domains revealed a much more detailed pattern.
Mothers provided greater investment in direct care and domestic support, bonding and emotional support, social and moral guidance, discipline and regulation, mating and relationship guidance, and wisdom and life guidance. These forms of investment were largely centered on caregiving, emotional support, and interpersonal development.
Fathers, by comparison, invested more heavily in athletics and physical training, as well as mechanical and practical skills. These domains were more closely related to physical development, technical abilities, and hands-on learning.
Sons and Daughters Received Different Types of Support
Rather than receiving identical forms of parenting, sons and daughters tended to receive support tailored to different areas of development.
Daughters received greater investment in mating and relationship guidance, protection, and material provisioning. This included advice about romantic relationships, efforts to promote safety, and practical assistance through resources and support.
Sons received more encouragement related to athletics and physical training, competitive behavior, and sexual permissiveness. Parents were more likely to encourage boys to participate in sports, embrace competition, and show greater tolerance toward their sexual behavior.
Parent and Child Sex Shaped Parenting Patterns
The researchers also identified interaction effects showing that the combination of parent and child sex influenced certain parenting behaviors.
Mothers devoted particularly high levels of investment to daughters in the area of mating and relationship guidance, suggesting especially strong involvement in girls’ social and romantic development.
Fathers showed stronger son-focused investment in athletics and physical training, as well as mechanical and practical skills, reflecting long-observed patterns of fathers participating in sports and practical activities with their sons.
Not every parenting domain differed by sex. Education and career support was provided at similar levels by both mothers and fathers and was offered equally to sons and daughters, indicating that parents generally shared similar expectations regarding their children’s academic and professional success.
Unexpected Findings About Competition
One of the more surprising findings involved competitive encouragement.
Based on evolutionary theory, the researchers expected sons to receive more encouragement to compete because male reproductive success has historically depended more heavily on competition and social status. The data supported this prediction.
However, it was not only fathers who encouraged boys to be more competitive. Mothers also tended to promote competitiveness more strongly in sons than in daughters.
Dougan suggested this pattern is consistent with the concept of inclusive fitness, which proposes that parents increase their genetic success through the success of their children regardless of the parent’s own sex.
Study Limitations and Future Research
The researchers caution that the findings should be interpreted carefully. The sample was relatively small and consisted primarily of participants from one region of the United States, limiting how broadly the results can be generalized to other cultures.
They also note that although the 13 parenting domains covered many important aspects of family life, they do not encompass every form of modern parenting. Areas such as digital supervision, online safety, and mental health support may require additional measures in future studies.
Dougan and his colleagues plan to develop a more comprehensive parental investment scale that can be applied across diverse cultures, including both industrialized societies and small-scale hunter-gatherer populations.
A More Nuanced View of Parenting
The researchers argue that parenting should not be measured simply by the total amount of time or resources parents devote to their children. Instead, parental investment consists of many different behaviors that may vary according to both the parent’s and the child’s characteristics.
This perspective offers a more detailed understanding of how mothers and fathers allocate their time, energy, and resources, while helping explain why certain parenting patterns appear consistently across generations and cultures.
Dougan emphasized that the study’s evolutionary explanations are intended to describe observed patterns rather than prescribe how parents should raise their children. The goal is to better understand why these differences exist, not to suggest that any particular parenting style is inherently better.
