about a month and a half ago i rescued a cat and did a long introduction with her and my other 2 cats, bella my alpha puss a year and a half old, chloe six months old, and tish about 2 years old. now at first things wernt going smooth alot of hissing growling pawing all that, i had to keep them seperated when i wasnt around but thing started to get better as time went on and they started to get along atleast live together, still some growles here and there but nothing serious. bella and chloe went back to being real close and they excepted that tish was here to stay. chloe and tish started to play with each other here and there and things where looking good. now tonight me and my wife left for about an hour when we left everything was fine when we came back the pusses all of a sudden hate each other again hissing,growling chasing each other all that!! what could of happened for them to all of a sudden not like each other again? i cant figure it out and im not sure what to do should i seperate them or should i let them work it out themselves? i dont know what to do HELP PLEASE!!!