Note about kid’s large family? (5)
I believe the answer is:
tribe
'large family?' is the definition.
(tribe can humorously mean a large family)
'note about kid's' is the wordplay.
'note' becomes 'te' (musical note).
'about' is an insertion indicator.
'kid' becomes 'rib' (I've seen this before).
'te' enclosing 'rib' is 'TRIBE'.
(Other definitions for tribe that I've seen before include "Native group" , "Social division" , "Israelites' division" , "Breed" , "Family - clan" .)