Sorry, kid. The binary is correct. The choice is one or the other, but not both. The choice is made at the moment of conception and is beyond the control of the mother, the father, or the child. This is how it works in nature.
Failure to recognize that is contrary to nature.
yep. And, in the exceptionally rare (1 in a million, if what I've read on FR is correct) cases where it is indeed "Both" or "Neither" .... we'll figure out a way to deal with it. No need to let a few hundred people hold an entire nation hostage.
Someone needs to explain to the kid, "Sometimes you don't like the cards you're dealt, but you still gotta play 'em." My guess is there's no Dad on the scene, or he's a neutered nebbish.