I don't know man. I got a nephew and something similar came up but it was nothing. Freaked me out. That's potentially life altering. I put a dress on once for Halloween because my good friend thought it would be funny, when I was about 12. Can't imagine a parent who turns that into "oh look she is being her true self lets ruin his life!!"

Very scary, man. Pray about it if that's your thing. Try to be a good role model. Take care of yourself and your life as an example. I guess. Really uncharted territory. I think i would honestly jeopardize my relationship with the kid's mother by telling her she's an insane piece of shit and she needs to stop immediately. No offense to your family.