so my aussie puppy and my whippet play together a lot but sometimes my whippet doesn't want to play/be bothered and the puppy keeps trying to play and herd her (nips at her back end). the puppy has drawn blood twice. how do i get the puppy to not do this? i've tried correcting her and seperating her but i don't want them seperated all the time. my husky plays with her sometimes and when the puppy gets too rough, he corrects her and she quickly stops and doesn't do it to him hardly ever. my whippet has thin skin/short fur so she is a bit delicate. she won't correct the puppy, she just lets it happen. any ideas on what i can do to stop the puppy from playing too rough?