> he child can't consent to medical procedures without a parent, today, and if the parent says no, the decision is deferred until the age of majority.

What does the parent's opinion have to do with it? Their opinion is equally ignored when it comes to statutory rape, no?

This is not a "this is a private matter between the child and the parent" scenario. Some things are, but a clear majority of people do not feel that this should be one of those things.