The boy, David, has an imaginary friend called Henry. David's mother was happy for him to have an imaginary friend when was very young but as he grew older she became more and more concerned about him. Is Henry an imaginary friend, or a ghost, or is David hearing voices?
David has exceptionally good academic skills and exceptionally bad social skills. David was bullied when he first started school. Henry lived in the next street to David but a century earlier. Henry fought in the First World War.
As for the girl, there is always more than one girl in any story.
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