Accept daughter married in small island (5)
I believe the answer is:
admit
'accept' is the definition.
(I know that accept can be written as admit)
'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' (an ait is a small island in a river).
'd'+'m'='dm'
'dm' going inside 'ait' is 'ADMIT'.
(Other definitions for admit that I've seen before include "Grant entry to" , "Provide student with place" , "Confess - acknowledge" , "Fess up" , "Take on" .)