New Cat Getting Along with Family Cat

I have had cats for about 15 years and integrated cats into the home. There are a couple scenarios to deal with and a couple of options.
First, make sure you have 2 sets of everything in different areas of the house. 2 litter boxes, 2 food dishes, 2 water bowls, 2 different sleeping areas, and 2 scratching posts. Your Calico feels threatened and it could take her/him up to 6 months to adjust.
Are both cats fixed and are they the same sex?
Sometimes cats don't get along like people. I had Jax, got Charley off the street, and Charley was terrified of Jax. Within a few weeks we brought in a female, she got attached to Jax-like he was hoping to have with Charley and Charley became the loner-he was very pleased being left alone. Sometimes it takes a 3rd cat to separate the issue.
The other thing, you may want to keep the new kitty isolated to a room or area of the house for a few weeks and slowly introduce the two for a few hours each day....tossing new kitty into the mix is a HUGE threat to Calico.
Talk to your vet, they can help too.

I have 2 cats (A brother and a sister) that have obviously been together all their lives. A few years ago when my family went on vacation, my grandma took one cat while the other cat stayed at home with my aunt. When we came home and reunited the cats it was like they didn't remember who each other was! They were constantly fighting, constantly hissing at each other. It was pretty much World War 3. At first we tried to get them to stop fighting, put them in separate rooms and what not. Then we just started ignoring them, cause it got to be too much work to get them to get along. Unless they are fighting to the point where it becomes a serious threat to one of their lives, just ignore it. After a couple weeks or a month or so, the kitties will get along. Make sure to give both cats equal attention though. When my best friend got a new kitten and brought it home where she already had a little older cat... Kitten was getting all the attention and older cat was getting jealous.

I recently had a similar situation. I had my cat and then my 2nd oldest daughter moved and I ended up with her cat, too. They BOTH hated each other and hissed. On top of that, my daughter's cat HATES dogs (I have two), so the poor thing was constantly hissing and hiding. I did keep her cat separated in a bathroom with her own potty box, food, etc for awhile and would also put her in there if I thought she was just having a tough day with all the hissing. It took about a month, but now they are both fine (dogs, too). I think the key is to give both cats a place to hide where the other cannot bug them. I also wouldn't force the situation by trying to get them together. Now, they sleep together and lick each other all the time, but my cat is very dominant with the other cat so they still squabble once in awhile.

I have added cats/dogs to my household numerous times over the years and I have never had a time that it simply just didn't work out. I'll bet after a few weeks, they will come to terms with each other - even if they never "like" each other.

Good luck and I am very sorry about your grandfather.

I got a few books from the library about cats by Pam Johnson that I really liked. She has a website too - Cat Behavior Associates.

Anyway, her advice on getting cats used to each other is to do it one sense at a time. So, at first you'd just have your Siamese in a closed room. They can trade a sleeping towel or something to get used to each other's scent. Also they are getting used to each other's sounds. You can also switch the cats between the two areas - put your Calico in the Siamese room and have the Siamese out to explore.

Once this seems to go well, have them see each other by giving treats or food at the same time with a gate between them. Then they are seeing each other and also associating each other with the good and happy event of food. This helps for positive associations.

Once this goes well, then you can leave the door open and let them come and go under supervision. It can take a few days to a few months, depending on their personalities.

Also, a rescue center, perhaps even a siamese rescue center should be kind enough to give you advice since they would want to see the cat in a home and not go into rescue either.

good luck! Siamese are sensitive, intelligent and wonderful cats.

p.s. we are allergic to domestic cats, but not Siamese. Sometimes people are allergic to a certain breed.

Put new kitty in her own room with her own litterbox. Keep them seperated. Do this for about 2 weeks. Your kitty will still have run of the house and get used to new kitty's scent. After the first two weeks, start taking new kitty out in a carrier and keep her in the carrier out in your kitty's living area for like a nhour at a time once or twice a day for several days. After that, see how your kitty handles the newcomer. Once she realizes she is not going to get hurt, lose food, or love from you, she will accept the new kitty. It takes time. My cat pouted for about 3 months when I brought another cat home. Now they are best buds who groom each other, play together and sleep together. When I took the new kitty to be fixed, my original kitty looked all over the house for him and cried and cried. Just give it time and everything will be just fine!