I don’t know where a kid would learn it unless brought up in a gay household.
Very beautiful stylish friend of mine has a lesbian daughter who hated dresses and dolls and everything feminine from the time she could walk and talk. They took her to shrinks and did everything to enhance her experience as a girl, short of giving her drugs, of course, and the kid just got more and more masculine with every passing year.
I lived in San Francisco for ten years. You cannot live in that city without having some gay friends, and I had several. As I got to know them, I observed that some of the gay men were gay by choice and others were just girls.
There were many moments of truth when the AIDS epidemic struck, with many gay men admitting they just LIKED being gay but now wanted to switch to heterosexual relationships. And they did.
Genetic? I really don’t know, but it seemed to be true for some of them.
Lot's o' reasons but most importantly is the child being given loving attention for the child's sake? V. beautiful and v. stylish have nothing to do with good parenting on the issue of gender orientation. One might say preoccupation with beauty and style directs focus of parent elsewhere than child causing child to attention-seek. Just saying . . . .