A story from my father's farm:
My father recently added two doggies to his family, in addition to the blue heeler he's had for many years. Well, big surprise, they sometimes fight. However, his skiddish (humans can't hold her) momma cat doesn't like them fighting, especially near her kittens. So last night, when the three canines got into it in the barn, she--according to eyewitnesses--ran at them, jumped onto the pile, then went flying off and away. It was not the first time she'd done something like that, and not the first time she'd succeeded in breaking up a fight of three much larger dogs.
The dogs may lack cordiality with each other, but they know who their boss is.
