Having married parents is good for children. That’s why the American Academy of Pediatrics (AAP) thinks that same-sex couples should be able to marry.

In a policy statement, that’s exactly what they said. It’s going to put the AAP in the middle of controversy–but it was the right thing to do for children.

There are currently almost 2 million children being raised by gay and lesbian parents in the United States. And you know what? They are fine. There is simply no evidence to suggest that it’s bad for children in any way to be raised by same-sex couples. They don’t have more emotional or social or any other problems than other children. For many of these couples, parenthood is something that they have chosen very deliberately and do with real commitment–and that is exactly what children need.

Whatever anyone’s beliefs are about parenting and same-sex marriage, we need to pay attention to the research. And research shows that what makes a difference in the well-being of children is the quality of the relationship they have with their parents, the quality of the relationship between their parents (or the significant adults in their lives) and the availability of resources, both social and economic.

That’s what matters, according to study after study. The sexual orientation of the parents just doesn’t.

And here’s the thing: marriage makes all of that more likely. As the policy statement says, marriage strengthens relationships and families. It brings 2 extended families together. Married couples have more financial and social resources. Married people tend to be healthier both physically and emotionally and less likely to do risky things. And marriage brings legal rights and responsibilities that are important–sometimes crucial, such as the right to make medical decisions.

This is about families. All children deserve to be raised in a secure, stable family that can give them the love, nurturing and resources they need. Marriage–not civil union or something else shy of marriage–helps give children all those things. Marriage supports families.

The AAP is hardly a hotbed of liberals. It is a huge organization with people from all sorts of different personal and political backgrounds. They don’t make policy statements unless they are absolutely sure that the scientific evidence supports them–and they only make policy statements that they think are really important for the health and well-being of children.

This is really important. It’s important for the 2 million children being raised by gay and lesbian parents. It’s important for the thousands of children in foster care who need loving families. It’s important for us as a society to do everything we can to support families–not just some families, the ones that look like us or that we agree with, but all families.

Because our children live in all sorts of families. And our children are our future.

Claire McCarthy is a primary care physician and the medical director of Boston Children’s Hospital’s Martha Eliot Health Center.  She blogs at Thriving, the Boston Children’s Hospital blog, Vector, the Boston Children’s Hospital science and clinical innovation blog, and MD Mama at Boston.com, where this article originally appeared.