Refuse to have young (6)
I believe the answer is:
litter
I believe this clue is a triple definition!
'refuse' is the first definition.
(I know that litter is a type of refuse)
'to have' is the second definition.
(littering is a kind of having)
'young' is the third definition.
(thesaurus)
(Other definitions for litter that I've seen before include "Do the kittens create rubbish?" , "little swine!" , "Pups - bedding - stretcher" , "Not a neat" , "Clean up the canine offspring?" .)