Possible Clues:

• Type of eternal youth
• Musical from Barrie play
• Safe to criticise one who never grew up
• After gym class, an upset parent gets him for Wendy
• Eternal child's favourite -- parent endlessly liberal
• Eternal youth in parent brought about by exercise
• Gym painter decorated, ignoring current show
• Darling visitor
• Saint subject to criticism? That's child's play
• Writer including apter parts rearranged for pantomime