That is also as it was explained to me when I registered the birth of my first son in Bangkok.
My 2nd son was born in the US, but his mom wasn't yet a US Citizen, so that 2nd son also isn't a NBC.
The 3rd son born in the US after his mom naturalized in the only one of the three eligible to be President.
Thanks, ASA Vet, for that info!
I recall someone here posting that, in the cases where children were born to American patents overseas, brochures were handed out to parents about the children’s status, and included was info about their ineligibility for the presidency.