Being a parent and having to deal with these issues is so so annoying. There is also the issue of the adult needing the toilet but the child (boy or girl) being too young to wait outside so you have to take them in with you smh.
I certainly do not mind seeing a dad with daughters in the women's restroom. And as a mum of boys i'm going to the women's restroom if they're young and i'm alone with them. BUT I also try to use those separate disabled toilets when possible and alone with my son.
Ok so here’s how it works
Dads with daughters: Women’s restroom.
Moms with daughters: Women’s restroom.
Dads with sons: Men’s restrooms.
Mothers with sons: Women’s restroom.
Hope that helps.