Miss Peregrine's Home for Peculiar Children is a contemporary fantasy debut novel by American author Ransom Riggs. The story is told through a combination of narrative and vernacular photographs from the personal archives of collectors listed by the author.
Ransom Riggs was born an American.
All we know about Ransom Riggs is that he/she is an American now. We do not know whether he was born an American or not. The system was probably guessing that if Ransom is now an American, that he was born one.