Experts have debated for decades how best to keep kids from abusing alcohol, with some insisting it’s better to allow teens to drink in moderation at home. This camps claims that allowing teens to consume alcohol within a structured environment makes booze less forbidden and subsequently less attractive for rebel-centric youth.

However, a new study suggests that a family’s rules concerning alcohol use aren’t nearly as important as the family itself.

For the study, published in the Journal of Studies on Alcohol and Drugs, researchers examined data from teens between the ages of 12 and 17. They found that teens who were allowed to drink at home actually had the lowest levels of alcohol use and abuse and had fewer problems later—but only if those teens were living with both biological parents. Those who lived with a single parent or a blended family had the highest levels of abuse and problems. Teens who weren’t allowed to drink at home at all fell in the middle of these two extremes regardless of their family structure.

It all comes down to familial stability, researchers speculate.

“An intact family structure with two parents might serve as a proxy for factors such as better communication with both parents and clearer expectations of behavior—what’s allowed and what’s not,” says Ash Levitt, a research scientist at the University of Buffalo Research Institute on Addictions and lead author of the study. “When there are two parents, it’s also easier to set rules and monitor how they’re being followed.” (Boston Globe)