It is especially dangerous for a yorkie under 5 lbs to have pups because she may be too small to whelp them. It is dangerous for any size yorkie to have a singleton because they could grow too large to whelp, best have the vet on stand by. If you could find some breeder available to help you out would be nice too but I dont think your dog is going to be able to free whelp I think she will need a c section |