Shine as good little creatures in a group (7)
I believe the answer is:
glitter
'shine' is the definition.
(synonyms)
'good little creatures in a group' is the wordplay.
'good' becomes 'g' (abbreviation).
'little creatures in a group' becomes 'litter' (group of young animals).
'g'+'litter'='GLITTER'
'as' is the link.
(Other definitions for glitter that I've seen before include "Are bright" , "Shine brightly, coldly" , "Flash" , "Twinkle" , "Glisten, sparkle" .)