Holden's relationship with Phoebe

Holden's relationship with his sister Phoebe is the only relationship Holden has where he doesn't act all superior. With other people, he constantly tries to put himself above them, so he can cut himself off from human interaction. But with Phoebe, he is unable to do that, because she is the only person he thinks isn't phony. Actually, she has the opposite effect on him, because in a way, around her, Holden's "superiority" is diminished and she becomes, in a way, the more mature one of the two, even though she's 6 years younger than him.