Dear teachers and friends:
Could you clarify the meaning of this sentence?
Talk to Peter Pan, who needs to sew his shadow back on!
Have you read the stories about Peter Pan? His shadow came off, and he had to sew it back on. It's obviously very imaginative.
I don't know what this author may mean in terms of using it as a metaphor.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.