Bless you for rescuing!
Muskrat is trying to dominate Bella. Most likely because she has weak energy so he does not respect her.
This is the way cats act when they are first introduced.They have a specific language they use to communicate with each other.
You do not need a behaviorist for cats. They are really quite easy to understand.
They do not rationalize, nor are they capable of in depth thought or reasoning.
Everything they do is basic, logical (to them) and makes perfect sense.
In a cat hierarchy a strong kitty will always try to take over and assume the head cat position. In addition, that is always subject to changes if cat one senses weakness in cat two. Cats DO work things out in their own way and they could care less what humans (or behaviorists) think. They only respond to the energy of another animal be it feline, canine or human.
If Bella acts scared and like prey Muskrat takes advantage and tries to bully her.
Your reaction is important because YOU are the final authority.
Cats do not follow a pack leader the way dogs do but they do sense their human parents energy and respond accordingly - so if you are nervous, they will be nervous. If you are stressed, they are stressed as well.
Sit down with a pillow. If Muskrat tries to bully Bella say NO! and gently push him back with the pillow.
You MUST be consistent! If you do it every single time he will soon understand his behavior will not be tolerated and go off to do something else. BUT anytime he approaches her nicely he gets an immediate food treat. That way he sees "good" behavior is instantly rewarded. When Bella sees Muskrat stopped she will gain confidence and no longer be afraid.
Then feed them side by side so she sees good things can happen when he is there.
Please let me know how things are going.
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