Daughter sent back inferior sink (5)
I believe the answer is:
droop
'sink' is the definition.
(to droop is to sink or sag)
'daughter sent back inferior' is the wordplay.
'daughter' becomes 'd' (genealogical abbreviation).
'sent back' is a reversal indicator.
'inferior' becomes 'poor' (similar in meaning).
'poor' written backwards gives 'roop'.
'd'+'roop'='DROOP'
(Other definitions for droop that I've seen before include "male problem?" , "Grow faint" , "Become limp" , "be despondent" , "Flag" .)