I'm staggered that this kind of professional advice is given and encouraged. Staggered. That getting onto the road of lifelong dependence on medication and irreversible surgery on your body is so casually recommended.
I was told a long time ago that children haven't changed, the world has. A wider exploratory into why this child is thinking this way and counselling is surely what a responsible adult would be advising.
Also, Joan of Arc dressed in men's clothing because she was a female knight and this is the clothing you would wear in battle to protect yourself. She's famously known for wearing men's clothing because this was used as a reason for her to be put to death (it was unlawful for women to wear men's clothing). There were also other lesser known warrior women throughout history.
Isn't it far more likely that the pious, bible wielding Joan of Arc had a Christian understanding of the 2 genders/sexes of women and men??
No, she looked and behaved a bit like a man, so she must be non-binary at the least. This is frankly getting a little insulting.