I wish I had some good answers for you but from my experience aggressive behavior like that is hard to break. It is very possible the aggression will get worse so watch them carefully. The best advise I have would be for you to talk to a dog trainer. How big is the yorkie and your other dog? I have had a couple of aggressive females over the years and the only thing that worked for me was to keep the aggressive ones separated. The coins in the can works sometimes but you can't always be standing there with a can in your hand. Also I would not leave them alone together when you are not home.
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"Lord grant me the serenity to accept the things I cannot change, the courage to change the things I can, and the wisdom to know the difference." |