He's married to your daughter (3-2-3)
I believe the answer is:
son-in-law
'he's married to your daughter' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for son-in-law that I've seen before include "Daughter's husband" , "Member of extended family" , "Relative by marriage" , "He's married to your daughter" .)