Own daughter married in small island (5)
I believe the answer is:
admit
'own' is the definition.
(I've seen this before)
'daughter married in small island' is the wordplay.
'daughter' becomes 'd' (genealogical abbreviation).
'married' becomes 'm'.
'in' indicates putting letters inside.
'small island' becomes 'ait' (I've seen this before).
'd'+'m'='dm'
'dm' going into 'ait' is 'ADMIT'.
(Other definitions for admit that I've seen before include "Recognise" , "Reveal" , "Confess - let in" , "Allow to enter; own up" , "Take on" .)