Mink's cousin
I believe the answer is:
stoat
'mink's cousin' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for stoat that I've seen before include "Weasel-like mammal" , "furry animal" , "Weasel, ermine" , "Source of ermine" , "European ermine" .)