To onlookers, Laura is just another Cathedral worshiper: A meek, submissive, quiet woman patiently following the lead of the rulers of the Cathedral. However, in reality, she is a spy for the Followers, focusing on finding out what is going on in the Cathedral so that the Followers can expose the wrongdoing. When she meets someone who has the pass phrase, she reveals an altogether different person: Bright, sharp, sarcastic, and strong.
↑Fallout Official Survival Guide p.104: "Laura: Apocalypse Spy" "When you first meet Laura-sometime after you've spoken with Nicole-she will speak and act like one of the Children of the Cathedral. She is, in fact, a member of the Followers of the Apocalypse and is working for Nicole, spying against the Children. While in the guise of a believer, she is meek, submissive, and quiet; once convinced through a password that the player was sent by Nicole, she is bright, sharp, sarcastic, strong, and wary."