Grill family’s fruit (7)
I believe the answer is:
pumpkin
'fruit' is the definition.
(I've seen this before)
'grill family's' is the wordplay.
'grill' becomes 'pump' (both can mean to interrogate).
'family' becomes 'kin' (synonyms).
'pump'+'kin'='PUMPKIN'
(Other definitions for pumpkin that I've seen before include "Orange-yellow fruit" , "big, yellow, and round" , "It's a Halloween tradition" , "Big squash" , "Halloween vegetable" .)