“Her light is growing faint,” Peter says, “and if it goes out, that means she is dead! She says…” Dramatic pause. “She thinks she could get well again if children believed in fairies!”
The children in the audience stir, surprised, as Peter Pan turns to implore them from across the footlights. Their attention isn’t enough, all of a sudden. “Do you believe in fairies?” he asks them. “Say quick that you believe! If you believe, clap your hands!”
They clap, of course. What else could they do? J.M. Barrie has constructed a dramatic trap that snaps shut on every kid in the theater: if Tinker Bell dies, then you personally are an asshole.