It’s increasingly well recognized that children’s first years of life exert a profound, lasting influence on their healthy development and later academic achievement. Indeed, according to a study published this summer, the social and emotional skills kids show as early as kindergarten are linked to their educational attainment, employment, substance abuse, and criminal activity fully twenty years down the road. And the roots of children’s aggressive and bullying behaviors may go back even further to preschool and the toddler years, a new Child Trends report shows.

That means that preventing bullying requires more than addressing school environments and regulations. It also must involve parents. As Deborah Temkin and Kyle Snow sum up the report’s findings of Child Trends:

Parents’ treatment of each other, their children, and others influences how young children treat their peers. Specifically, parents’ use of harsh discipline and children’s exposure to domestic violence are related to increases in bullying behavior, while parents’ positive engagement in their children’s lives, such as through interactive play, reading, and meals together, seems to be protective against bullying behavior. Parents serve as role models for their children, and modeling empathy, concern, and care for others may help deter later bullying.

But as the researchers note, many of the studies in this sphere focus on mothers rather than fathers; there is a “notable void in the literature” when it comes to fathers and bullying. And given what we know about how fathers influence kids’ behavior and social skills, that’s a major problem.

For instance, a slew of studies underline that kids with absent fathers engage in more externalizing behaviors, meaning they are more aggressive and more apt to fight or break rules than kids whose fathers are present. Sara McLanahan, Laura Tach, and Daniel Schneider have shown that this difference is not just due to selection.

Furthermore, as Paul Raeburn has documented, dads play a major role in teaching kids to play and get along with their peers. Scholars found in the mid-twentieth century that children whose fathers were absent for long periods in their early childhood were “less popular and (hardly surprisingly) less satisfied with their relationships with their friends.”

It’s not only fathers’ presence that matters, however. Their particular parenting behaviors make a difference. According to a later study, three- and four-year-olds whose fathers “engaged in the most physical and enjoyable play” were rated by their preschool teachers to be the most popular with their peers. Similarly, drawing on the research of Ross Parke, Raeburn notes that “Children whose fathers took turns being the one to suggest activities and showed an interest in the child’s suggestions grew up to be less aggressive, more competent, and better liked. These were fathers who played actively with their children, but were not authoritarian; father and child engaged in give-and-take.”

Such findings don’t prove that good dads can help prevent their kids from growing up to be bullies. But that possibility sure seems to merit greater attention from researchers.