Something like that happened to me a few years back lined my best white Jill to my mates hob, due date came and a kit was hanging out of her so a trip to the vets, an injection to help with the contractions and 5 more kits 2 alive 3 dead, I kept them both a hob and Jill, both of which have made good working ferrets, but the vet advised me not to bred off the mother again.