I don't know if it's the right section here, but I wanted to know if the following is a (common) japanese phrase, or rather a literary expression of the author of the novel I'm reading? (I wonder if it could be a hidden hint of the origin of the character, but if it's "only" a common phrase, it wouldn't.)
生まれたときからその場にいたような(顔で)...
(with a facial expression) as if he had been there since (his) birth...
生まれたときからその場にいたような(顔で)...
(with a facial expression) as if he had been there since (his) birth...