Daughter gets sheep to drink (4)
I believe the answer is:
dram
'to drink' is the definition.
(small alcoholic drink)
'daughter gets sheep' is the wordplay.
'daughter' becomes 'd' (genealogical abbreviation).
'gets' says to put letters next to each other.
'sheep' becomes 'ram' (male sheep).
'd'+'ram'='DRAM'
(Other definitions for dram that I've seen before include "Small drink of spirits" , "Small drink of scotch" , "Tot of whisky" , "little weight" , "Small drink (Scots)" .)