Sandie, I'm sorry to hear this. My Storm who is the alpha cat will still bully Sky and Ziggy for no reason at all. I would also agree that if you have a spare bedroom, then try setting up a litter box and a food and water dish in there for Mandy. The only other thing would be to give Tommy and Crystal some kind of calming meds or herbs so that they won't be such bullies. I'm sure you've aleady tried Feliway plugins and spray. I used to use them and my cats became desensitized over time so they didn't work any more. Now I just try to give Storm a time out or break up the fight/squabble the best I can. Good luck.