Genetics determine a lot about who we are, but parenting styles and practices have an equally strong influence. No one questions the importance of a mother's love in her children's physical and emotional development. As it turns out, we also shouldn't question the importance of a father's. Rejection Changes Who a Child Becomes A recent study from the University of Connecticut shows that a father's love is critical to his children's personality development. No childhood experience has as profound effects on personality development as rejection by their parents, researchers say. Children who are rejected in this way tend to struggle with anxiety, insecurity and aggression toward others, not only as children but also as they grow into adults. This history can set them up for difficulty in their romantic relationships later in life. To the human brain, rejection is the equivalent of physical pain, but as co-author Ronald Rohner pointed out, unlike physical pain "people can psychologically re-live the emotional pain of rejection over and over for years." Is a mother's love alone sufficient for healthy personality development? Perhaps, but a review of more than 500 studies suggests that the influence of a father's rejection can be greater than that of a mother. According to psychologists working on the International Father Acceptance Rejection Project, if children perceive their father as having more power or prestige, his influence may carry more weight than their mom's. Thus a father's rejection could have an even more significant lifelong impact. Involved Dads Raise Smarter, Better Behaved Children Previous studies have shown that a father's involvement plays a critical role in his children's academic performance and behavior. A 2011 study from Montreal's Concordia University showed that children whose fathers were actively involved in their upbringing had fewer emotional and behavioral problems, better problem-solving skills, and higher intellectual abilities. In the study, girls were more profoundly affected by an absent father than boys. According to Penn State associate professor Valarie King, it's the quality of father-child interactions that matters most. Stepparents can have close, beneficial relationships with their stepchildren, and fathers who live outside the home still have a significant impact on their children's development if they stay actively involved in their lives. "The closer the father-child relationship \u2013 not just the amount of visitation \u2013 the better children were doing," said King. To grow up confident and well-adjusted, children benefit from close relationships with their fathers. Whether he is at home or not, his influence matters more than he may realize. As Father's Day approaches, lend nurturing support and acceptance to your children. It may not seem life-altering in the moment, but your interactions affect who your child is today and for the rest of their lives.