Relative quiet with fellow entertained by novel (6)
I believe the answer is:
nephew
'relative' is the definition.
(type of relative)
'quiet with fellow entertained by novel' is the wordplay.
'quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'with' is a charade indicator (letters next to each other).
'fellow' becomes 'he' ('he' refers to a man).
'entertained by' means one lot of letters goes inside another (inserted letters are hosted or entertained).
'novel' becomes 'new' (novel means new or fresh).
'p'+'he'='phe'
'phe' going inside 'new' is 'NEPHEW'.
(Other definitions for nephew that I've seen before include "A sibling's child" , "Brother's/sister's son" , "Sibling's son" , "Edward V to Richard III relation" , "A young male relation" .)