Kid associated with Creep singer (9)
I believe the answer is:
chaffinch
'singer' is the definition.
(chaffinch is a kind of birdanimal)
'kid associated with creep' is the wordplay.
'kid' becomes 'chaff' (synonyms).
'associated with' says to put letters next to each other.
'creep' becomes 'inch' (I've seen this before).
'chaff'+'inch'='CHAFFINCH'
(Other definitions for chaffinch that I've seen before include "Singer" , "Common bird" , "Small European songbird" , "European bird with black and white wings" , "Garden bird" .)