Explain using quotes from The Catcher in the Rye how Holden's internal conflict of not wanting to grow up and wanting to prevent others from growing up results positively because it results in Holden growing up due to his responsibility of Phoebe.
Holden is, above all else, a very confused young man. This confusion expresses itself primarily in his reluctance to grow up and his attempt to keep everything the same. It is highly significant that he finds the mummy exhibition in the museum a very peaceful place, because it represents what he is trying to achieve in both his life and in the lives of others: a stasis, or a place where time pauses and does not advance. Holden best expresses his desire not to grow old and to prevent children such as his sister from growing old in the following quote where he relates himself to the "catcher in the rye":
Anyway, I keep picturing all these little kids playing some game in this big field of rye and all. Thousands of little kids, and nobody's around--nobody big, I mean--except me. And I'm standing on the edge of some crazy cliff. What I have to do, I have to catch everybody if they start to go over the cliff--I mean if they're running and they don't look where they're going I have to come out from somewhere and catch them.
Of course, what Holden realises is that this role of being "catcher in the rye" involves responsibility towards the children that he desires to save. This therefore means that he can't simply run away and leave Phoebe by herself, as she would therefore be left without anyone to metaphorically "catch" her in the terms that the song uses. There is a huge irony in Holden's interpretation of the song, which is actually about casual sex (precisely the opposite of what Holden wants to save children from), but it nonetheless serves to highlight Holden's growing sense of responsibility towards his sister which means that he is unable simply to leave and run off.