Ever know a guy who didn’t truly grow up until he gazed into his baby’s eyes? (Maybe it's even the case with your own husband?) There’s something about holding a precious newborn that can turn even the baddest of bad boys into grown ups who embrace fatherhood. In fact, that’s the finding of a new study in the current issue of the Journal of Marriage and Family, conducted by researchers from the Oregon State University and the University of Houston. Fatherhood, it turns out, is often the strongest catalyst for men to clean up their act, according to the 19-year study that followed 206 men from the time they were fourth grade delinquents. After having a baby, the new dads in the study decreased their tobacco use, alcohol consumption, and committed fewer crimes. This was especially true for those who had their first child in their late 20s and early 30s, more so than those who fathered children in their late teens or early 20s. "This research suggests that fatherhood can be a transformative experience, even for men engaging in high risk behavior," explains David Kerr, assistant professor of psychology at Oregon State University and lead author of the study in the university press release. "This presents a unique window of opportunity for intervention, because new fathers might be especially willing and ready to hear a more positive message and make behavioral changes." Whether your hubbie is a reformed bad boy or a boy-next-door type, it’s encouraging and kind of sweet to draw the conclusion that having a child will likely have a positive influence on him. And if he was a handful growing up, just think of how that can translate into parenting advantages: He’ll make sure his kids have better opportunities than he had, he can offer "been there, done that" advice, and, best of all, once the teen years roll around, he’ll be able to spot a shaky excuse a mile away.