I recently brought a new kitten into my house with my 13 year old cat who has ALWAYS been an only cat (with the exception of a few months when I lived with a boyfriend). Like others said (and my vet agreed with this too) I put Paizly in her own room, mainly because she hadn't had her shots too. But then even after her shots I kept her in her room and Zoee met her within the first week. But Taz was able to come by the room and sniff under the door. Paizly did hide a little at first too. But we would just go into the room and lay on the floor. She eventually would come out to investigate us. We'd play with her and talk to her. We let her come to us when she was ready.
Eventually we let her out into the rest of the house under close supervision. Taz hated her! Hiss, growled and swatted at her constantly!! Then about a week later they were actually playing together. Even now, especially with Taz not feeling good, he still hisses and growls at her quite a bit. But I never interrupt, I only watch to make sure it doesn't get out of hand. The thing is, Paizly has no fear! She'll just keep coming back for more. LOL

I felt horrible that I had turned Taz's world upside down by bringing home a little monster (his words LOL). But they are all fine now. And Zoee gives Paizly baths all the time too. Basically you just need to give them all time. I honestly felt like there would never be harmony in my house again. But experienced PTers put my mind at ease and of course they were right!!

I'm looking forward to seeing pictures of Olivia. And I'm also looking forward to hearing about how well they are all doing in about a month.