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.
Penny displays weak energy hence the two aggressive males do not respect her.
In every relationship there must be a leader. The others are followers.
The head cat is a benign leader thus I know one of the quiet, accepting males is the alpha.
The two bully males are trying to dominate Penny, especially the one that bites her on the neck.
You cannot separate the cats because then you break up the pack and delay their bonding. You must take over because YOU are the final authority. They will all listen to you!
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.
So you must remain as calm and positive as you can muster. If you emit positive thoughts like " I just KNOW all these cats are going to get along" they WILL!
Sit down with a throw pillow. If any cat approaches Penny in an aggressive manner say NO and gently push him back with the pillow.
You MUST be consistent! If you do this EVERY SINGLE TIME they will understand that their behavior will not be tolerated. BUT any time they approach nicely, they get an immediate food treat so they see GOOD behavior is instantly rewarded.
Please let me know how things are going. If you have any questions along the way, I will always be here for you.
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