Listen up, Dads. The closeness of your relationship with your teen and your attitudes about teen sex have a huge influence over their sexual behavior. Kids who are emotionally close to their dads tend to start having sex later than those with more strained relationships. And dads who approved of early adolescent sexual activity had kids who started sex younger than dads who thought teens should wait before having sex.

In a 2011 study, the Centers for Disease Control and Prevention (CDC) found that just under half of high-school students (47%) had had sex, and 40 percent of those who were doing it didn’t use a condom during their last intercourse.  That’s exactly the kind of risky behavior that leads to pregnancy and sexually transmitted diseases (STDs).

The results of this new study weren’t really surprising—other research has shown that when parents communicate with their teens about sex, the teens are less likely to engage in risky sexual behavior. The difference here is that in this study, the researchers had the common sense to actually include fathers (almost all other studies on the topic have asked only mothers).

So the father’s role in influencing teen sexual behavior is independent of the mother’s.  And  what’s especially interesting is that dads who are either extremely strict or extremely lenient end up having kids who start early. Dads who are consistent, rational, give their teens a reasonable amount of autonomy, and establish clear consequences for breaking the rules, have kids who have sex later.