Regard daughter as offspring (4)
I believe the answer is:
seed
'offspring' is the definition.
(I've seen this in another clue)
'regard daughter' is the wordplay.
'regard' becomes 'see' (synonyms).
'daughter' becomes 'd' (genealogical abbreviation).
'see'+'d'='SEED'
'as' acts as a link.
(Other definitions for seed that I've seen before include "From which things grow" , "It can develop into a plant" , "Grain" , "Pip - source - children" , "An outstanding player in a tournament" .)