introducing a new cat

Hi, I'm new here and could use some advice. My husband and I have been considering adopting two new kittens...a brother and sister that need to be kept together. We have had our cat for two and a half years now and she's the sweetest cat I have ever seen. I don't think she knows how to use her teeth or claws But, we're worried that getting more cats would change her. When we had another cat stay at our house for a couple days last year, she seemed like a different cat. We heard her hiss for the first time ever and she hid under the couch and would not come near us until the kitten was locked in another room. We know that we would need to be patient and that she would be upset at first, but we're wondering if there are just some cats that have to live by themselves. We want her to still be same affectionate, lap-loving cat that she is. My husband especially is worried that she won't sit and cuddle with us like she does now if there are more cats in the house. I could really use any advice you have...I love kitties and really want to adopt these two.

Thanks so much,
Natalie

I've never had to introduce cats to each other myself but I believe you have to take the intro's slowly.
Firstly have a room prepared for the new kittys with bed, litter, food & water & toys. Keep them in this room for at least a week & don't let them out. Your cat will be able to smell the new kittens.
Next you can let the kittens out into the rest of the house when your cat isn't there. They'll each get each others scent from around the house.
Then you let them into the same room but apart so they can just see each other. You then let them be with each other under supervision.
This process may take a few weeks, but its worth it in the end.
I may have left some steps out, but someone else may be able to help you.
Good luck!!!!!

I've been doing research about the best way to introduce cats and I do think that my cat probably would get used to having kittens around...I just don't want her to start hiding all the time or change her personality. My husband is especially worried...it really upset him to hear her hiss for the first time. So now I'm trying to convince him that she would be fine after a while and that we have to be patient with her...I really, really want more kittens

I really can't give advice on this as Radar and Sonic are still not completely comfortable with each other despite my wife and I making a 100% effort. We kept them apart and let Sonic have his own territory before exchanging clothes with each others scent on, letting them explore each other 'territories' and then letting them see each other whilst in cat carriers. We have had them share toys, share food and played with them together...
It has been a slow process but they still fight/wrestle constantly. I expect things will improve in time and it is heartening that when one cat is removed from the room the other seems to be in mourning- especially Radar who seems desperate to groom Sonic

My advice is that try suggestions on this thread but expect it to be a long hard slog, though I know other posters who have had no problems at all. Go figure!