We have three cats (Sasha-8, Whisper-5, and Peanut-2). We brought Bella home almost two weeks ago, and so far, Sasha seems to HATE her. Not afraid, just pure dislike. I don't think she's afraid because she'll just walk by her and hiss... It's kind of funny. What's even funnier (but maybe in a not-so-good way is that Bella has started growling when Sasha gets near.
Peanut and Whisper on the other hand are still a little afraid of Bella. They'll come around and love to watch her, but when they get to close, Bella gets excited and starts hopping and bopping around, and the cats run away. I can tell they wanna play together and I hope sooooooon they will.
Good luck!