I understand that. I actually have old friends who are in that boat. They are gay men who had twin boys via a surrogate mother in the 1990's, when they were already in middle age. That was groundbreaking then! The stories they tell of navigating Cub Scouts and soccer leagues circa 2003 with their boys would make you laugh and cry at the same time.
But I am also adept enough at statistics to know those families are still a
tiny, tiny minority of the American population. Even today.
Thinking back on my babysitting days when my nephews were young, I just don't think I wanted to wade into that topic with them. It wasn't my place. It wasn't appropriate. It was inherently sexual, and that's simply not okay to discuss with children. Especially children who are not your own.
My sister told me that she explained my sexuality and why I didn't have a wife to her boys individually, both when they were mid-teens. Both boys went "Oh, I get it!". They may have already known for a year or two based off of scientific information learned on the play ground, but they at least played it off as though Mom was letting them in on a family secret and admitting them into a more mature stage of life.
I should ask them sometime! (Dammit, they already left and flew back home from their Christmas visit!)
But I certainly wasn't going to bring it up. That was her job, her responsibility, her right as the parent.
I mentioned it earlier, but it sort of meshed around in my brain over dinner just now. I think Disney is having problems with pushing cultural envelopes. It's just not been their brand or their business model for the past 100 years. Parents are hesitant to let Disney do that for them. I think Burbank needs to rethink their business strategy on pushing cultural boundaries with their children's films.
Leave that stuff for PG-13 or higher, if they feel the need to do it. It's clearly not working well for them at the PG animation level.