My jack russell and yorkie fight, well actually, my yorkie hangs on my russells leg and he drags her around. But when hes had enough, he growls and nips her scruff, then she goes on her back and licks him like crazy. In a few shes at it again. But really Ive noticed mostly they take care of their own pack order. It really all depends on how you raise them and if they have good temperment.
