Come together! See lambs frolicking! (8)
I believe the answer is:
assemble
'come together' is the definition.
(I've seen this before)
'see lambs frolicking' is the wordplay.
'frolicking' is an anagram indicator.
'see'+'lambs'='seelambs'
'seelambs' is an anagram of 'ASSEMBLE'.
(Other definitions for assemble that I've seen before include "Put together all the components" , "Meet" , "Bring/come together" , "Bring or gather together" , "Collect in one place" .)