Hi everyone. I'm new to this forum. I have really liked it here. I have a huge problem.. My 2 month old german shepherd keeps biting my 1 year old Jack Russell Terrier. Boo, the GSD keeps jumping on top of my Jack Russell and biting his neck (REALLY HARD, HIS TEETH ARE LIKE STAPLES!) well, the J.R either attacks him back or just lets him bite his neck and tail and leaves him.. Please how do I stop this? I cage the german shepherd because he is always biting my other dog. The J.R is very calm while the GSD all he does is bite the J.R. Please help me. Thank you so much.