This is why I support trans people in describing themselves as whatever they want to, and I strongly discourage body modification (but it is their right to choose to modify if they us e their own money/insurance and they know what they are consenting to).  I am horrified by kids being tricked into mutilating their bodies without any capacity to understand what they are doing and what kind of trade-offs they are making. 

 And it has nothing to do with age. It has to do with your ability to give informed consent. Rapey vibes from anyone who believes they know what is best for a child before the child can consent. Fuck those people.