I agree that it is possible for two loving people to be able to raise a child. Come on, Rambler, even a scientist has to know that the best thing for a child is a mom and a dad. Do you have the stats on prisoners? I think it is something like 80% have one thing in common -- no dad to serve as a role model. A man and a woman really do bring something different that a child needs.
I said it was a good working hypothesis. But I have two more thoughts about this.
One is that showing no dad is bad might show something about single parent families rather than about same-sex two-parent families. I'm saying might.
The other is this thing I'm starting to wonder about but haven't formulated quite yet. It has to do with whether we want to specify what makes the "best" family and then rule our other types of families.