Huh... I wonder if there could be some sort of intervention therapy that could keep them a girl, in that case, or if it's really set in stone that they will transform.
If so, there could actually be a sort of "third sex" on the horizon. It's been explored quite a bit in sci-fi tropes, but amazing that it's actually (kind of) real!
Imagine if you literally got to choose your sex, with no preset arrangement... you were just a "third gender" type, then elect to go through either male hormone or female hormone therapy depending on your druthers.
If so, there could actually be a sort of "third sex" on the horizon. It's been explored quite a bit in sci-fi tropes, but amazing that it's actually (kind of) real!
Imagine if you literally got to choose your sex, with no preset arrangement... you were just a "third gender" type, then elect to go through either male hormone or female hormone therapy depending on your druthers.