Massacre, having family to get rid of (9)
I believe the answer is:
bloodshed
'massacre' is the definition.
(I know that bloodshed is a type of massacre)
'family to get rid of' is the wordplay.
'family' becomes 'blood' (blood can mean one's family).
'to get rid of' becomes 'shed' (shed can mean to get rid of or discard).
'blood'+'shed'='BLOODSHED'
'having' is the link.
(Other definitions for bloodshed that I've seen before include "Indiscriminate slaughter" , "Carnage" , "The killing or wounding of people, very gory" .)