What should I do with my Dog?

Ok, you should have gotten Sable trained a long time ago. Herding dogs have a strong prey drive and it needs to be controlled. When Sable and Brandi were fighting in the beginning you should have gotten rid of Sable. Brandi had to go trough pain and suffering in the end because of it. Im sorry it happened, I really am. It was just a poor decision to keep Sable.