Fun family member receiving a kiss (10)
I believe the answer is:
relaxation
'fun' is the definition.
(I've seen this before)
'family member receiving a kiss' is the wordplay.
'family member' becomes 'relation' (a relation or relative).
'receiving' is an insertion indicator.
'kiss' becomes 'x' (X can represent a kiss).
'a'+'x'='ax'
'relation' going around 'ax' is 'RELAXATION'.
(Other definitions for relaxation that I've seen before include "fun" , "repose" , "(Period of) rest" , "leisure" , "Chilling out" .)