They’re doing more than cracking dad jokes. A new study suggests a father’s parenting behaviors in the early years of a child’s life may shape their physical health years down the line. But in a surprising twist, researchers found no similar link when it came to mothers. “The lack of clear results based on the mothers’ coparenting was not expected,” Jennifer Graham-Engeland , a professor of biobehavioral health at the Penn State College of Health and Human Development and co-author of the study,