Silly daughter going behind (3)
I believe the answer is:
aft
'behind' is the definition.
(aft means towards or at the end of a ship)
'silly daughter going' is the wordplay.
'silly' becomes 'daft' (I've seen this in other clues).
'daughter' becomes 'd' (genealogical abbreviation).
'going' indicates named letters should be taken away.
'daft' with 'd' taken away is 'AFT'.
(Other definitions for aft that I've seen before include "Farther back on board" , "Toward's a ship's stern" , "Sternward" , "Towards the rear at sea" , "back to sailors" .)