Possible Clues:

• American thug conceals detective is a prot?g? of Mafia boss?
• Requires a sponsor to bully detective undercover
• Baptized boy
• Sponsored boy at a baptism
• No dogs (anag)
• Go and nods with a child that's not originally your own
• Child with a sponsor, maybe
• Medal cut includes award, a sponsored one
• Boy sponsored at baptism
• Do take him on in song