Milk supplier sure went crazy (3,5)
I believe the answer is:
wet nurse
'milk supplier' is the definition.
(I've seen this before)
'sure went crazy' is the wordplay.
'crazy' indicates an anagram.
'sure'+'went'='surewent'
'surewent' with letters rearranged gives 'WET-NURSE'.
(Other definitions for wet nurse that I've seen before include "Milk supplier" , "Child-minder" , "Woman employed to suckle" , "Coddle" , "Woman feeding another's baby" .)