So my niece was born a boy. An identical twin at that. From as early as they could express themselves she wanted to hang out with her older sister, play with dolls, paint her nails, play princess, etc. Her brother is such a typical boy: loves sports, fighting, army stuff, etc.
Then came the questions: why do I have a penis? I don't want it. Can I be Dorothy for Halloween? Will my penis go away? Mommy did you used to have a penis?
Then came the kids at school making fun of her for wanting to play with girls, doll, etc. She asked for a My Little Pony shirt when she was like 6 and then when we got it for her she cried and said she didn't want it anymore- she wanted Ironman stuff so the kids at school would be nice to her again.
When she sees old pictures of herself, she asks did I have a penis then too? Does god sometime make mistakes with babies?
Then came depression and saying she wanted to die. Anyway she is in 2nd grade now, fully functions in society as a girl. Still is in therapy, has been to transgender camp and is getting better with her self esteem.
There is zero doubt in my mind Kate is a girl and always was.