I came home and as usual the dogs were excited. I petted each of them and put a few groceries away as I normally would. I had to go bathroom real bad and while I was going, I heard our senior crying out and after having her for 13 1/2 years I knew it was a cry of pain. I ran out of the bathroom and found Kodiak harassing her as she was spread eagle on the rug in obvious pain. So I grab Kodiak by the collar and pulled him off and then helped Denali get back on all fours. She was limping for awhile but now seems ok. I don't know if Kodiak was trying to play or dominate her. He seems to snip at her everyonce in awhile especially when biscuits are involved. This is a new behavior out of him towards her so i am not sure what to make of it. Any suggestions on what to do to protect her since Kodiak is big enough to hurt her?