Before we meet Phoebe, Holden’s side of the story is all we’ve been given. He implies that he is the only noble character in a world of superficial and phony adults, and we must take him at his word. There seems to be a simple dichotomy between the sweet world of childhood innocence, where Holden wants to stay, and the cruel world of shallow adult hypocrisy, where he’s afraid to go. But Phoebe complicates his narrative. Instead of sympathizing with Holden’s refusal to grow up, she becomes angry with him. Despite being six years younger than her brother, Phoebe understands that growing up is a necessary process; she also understands that Holden’s refusal to mature reveals less about the outside world than it does about himself. Next to Phoebe, Holden’s stunted emotional maturity and stubborn outlook seem less charming and more foolish. Phoebe, then, serves as a guide and surrogate for the audience. Because she knows her brother better than we do, we trust her judgments about him. Our allegiance to the narrator weakens slightly once we hear her side of the story.
Phoebe makes Holden’s picture of childhood—of children romping through a field of rye—seem oversimplified, an idealized fantasy. Phoebe’s character challenges Holden’s view of the world: she is a child, but she does not fit into Holden’s romanticized vision of childlike innocence. Although she never explicitly states it, Phoebe seems to realize that Holden’s bitterness toward the rest of the world is really bitterness toward himself. She sees that he is a deeply sad, insecure young man who needs love and support. At the end of the book, when she shows up at the museum and demands to come with him, she seems not so much to need Holden as to understand that he needs her.