Free to follow a family member (6)
I believe the answer is:
'family member' is the definition.
(I've seen this before)
'free to follow a' is the wordplay.
'free' becomes 'untie' (I've seen this before).
'to follow' means one lot of letters go next to another (some letters go after or follow others).
'untie' after 'a' is 'AUNTIE'.
(Other definitions for auntie that I've seen before include "Close relative" , "BBC; relative (colloq,)" , "Relation; the BBC" , "The Beeb" , "Unite a strange family member" .)