Board Thread:General Discussion/@comment-24674051-20150605195047/@comment-4839682-20150606192224

Emma is not legally Henry's mother, she gave up that right. Of course, things are different in Storybrooke. It's more like divorced parents sharing custody. In that kind of situation, it's pretty common for the child to want to spend most of their time with the parent they've never really known. Plus, all that turmoil during Season 2 with Regina's struggle against her evil side.

Regina is Henry's mother. Emma is too, but Regina has done far, far more.