| Without knowing your sisters dog and it's level of socialization with other dogs I wouldn't say it's good for your puppy to get bit by it. But with a dog that is socialized - it is good for your puppy to be taught acceptable behaviour. An adult will first growl their displeasure, then bares it's teeth, if still no response then they will nip. The nip on a socialized dog will not "hurt" the puppy physically but will make it step back and pay attention to the growls and teeth baring.
__________________  If you want to make a small fortune breeding dogs, start with a large fortune. |