Then you really need to read up on it. In no particular order, these are a few that I've come across recently. Following names and key words will bring you upteen articles and blogposts on these issues. I don't believe any of these below touch on the issue of the as yet unknown effects of hormone therapy on children, which is another controversy.

https://www.theatlantic.com/magazine/archive/2018/07/when-a-child-says-shes-trans/561749/

https://jezebel.com/whats-jesse-singals-fucking-deal-1826930495

http://www.sexologytoday.org/2016/01/do-trans-kids-stay-trans-when-they-grow_99.html

The issue of desistance is a hotbutton topic right now:

Zucker: The myth of persistence: Response to “A critical commentary on follow-up studies and ‘desistance’ theories about transgender and gender nonconforming children” by Temple Newhook et al. (2018)

Above is part of a back and forth in the journal International Journal of Transgenderism

https://www.thecut.com/2016/02/fight-over-trans-kids-got-a-researcher-fired.html