Possible Clues:

• Exercises parent organised as play for children
• Permanently immature playboy?
• Flag on vessel as young as ever?
• Youth forever exercises worried parent
• Safe vessel for voyager to Never Never Land
• Story that begins 'All children, except one, grow up'
• The little boy who never grew up
• Neverland resident
• Barrie boy
• It's safe to excoriate Barrie's work