And try this for a scenario... A single woman gets pregnant and for-whatever-reason the father won't be involved. To make life a little easier, she moves in with her mother, who for-whatever-reason happens to be single. So a household of mother and grandmother raising the child.
Would your friends object to this?
How much different is this than two female partners raising a child together?
I wouldn't say it's the norm, but many of the people I know in same-sex relationships tend to have one more masculine and one more feminine. I'm thinking that a child would still get the good and bad from their parents just as kids of straight couples do. And if a single parent can raise kids, then a co-parenting unit can too.