Very angry cat

Question
My older female, Cocoa, is about five or six years old and neutered. She never had attitude problems with my even older female cat, Rosie, or me. She always came when you called and obeyed. But when Rosie died, I got a new female kitten named Hailey. I knew Cocoa would'nt get along right away, but Hailey is already about six months and Cocoa is still very angry about her being there. She began protesting by staying outside and hissing at the slightest scent of Hailey. Cocoa only once tried attacking her, but that was because Hailey suprised her. Cocoa's attitude lightened slightly, as she would spend more time in the house and tolerate Hailey more, but it is at its worst, now that Hailey is pregnant. I barely see Cocoa, because she's always roaming the neighborhood. I recently carried her into the house, while Hailey was inside, and once she got in, she would have none of it. Cocoa will hiss and growl and fuss untill I let her out. She won't even drink milk around Hailey anymore. I know Cocoa will never befriend Hailey, but I want them to at least be able to be in the house together without Cocoa making a racket. And with kittens on the way, I don't imagine it will get much better.
Sincerely,
Rebecca

Answer
Hi Rebecca,

I am saddened to hear that your 6 month old kitten is pregnant already, did you not get her spayed in time or did you breed her on purpose? Do you have homes picked out for all the kittens and plans to get them spayed and neutered as well as Hailey?

First of all, you need to spay Hailey if you want them to get along. Also unspayed females are subject to uterine infections and mammary cancer, and produce kittens of which hundreds are already killed every day in your local shelter since there are not enough homes. It is highly irresponsible to allow your unspayed female cat outdoors.

It's also much harder to convince cats to get along when they are allowed outdoors, also it is very dangerous for your cat to be out roaming the neghborhood. She could be hit by a car, poisoned or attacked by dogs. I highly recommend keeping your cats indoors only, or building an enclosure or cat proof fence - this article tells you more:

http://catnet.stanford.edu/articles/enclosures.html

As for getting your kitten and adult to get along, you should get Hailey spayed and then back up and introduce them more gradually again following the guidelines in this article:

http://catnet.stanford.edu/articles/introducing_cats.html