Reared animals for stage (4)
I believe the answer is:
step
'stage' is the definition.
(I've seen this in other clues)
'reared animals' is the wordplay.
'reared' says the letters should be written in reverse (in a down clue, letters 'rear up').
'animals' becomes 'pets' (pet is a kind of animal).
'pets' reversed gives 'STEP'.
'for' is the link.
(Other definitions for step that I've seen before include "Foot movement" , "'Stage, rung (4)'" , "Prefix meaning related by remarriage" , "Stride" , "bit of a dance" .)