“Whether you’re natural-born or not, I believe, is decided at birth.”
Except that adoption law is predicated on the legal fiction that a child born of one parents is the offspring, for every and all purpose, of the adoptive parents.
I can’t think of a case where a judge had ruled that adoptive children are to be treated differently than biological children. If a child who shared your DNA and has your name on the birth certificate he would be treated the same as a child who was adopted and had your name on the new birth certificate.
It sort of like a felon who has a presidential pardon. His slate is wiped clean, so he can vote, own guns and run for office even though he’s been convicted of a felony.