Older cat hates younger cat

I just moved into a new apartment with my two-year-old cat Maggie, and my new roommate has a 16-year-old Siamese named Blossom. We kept the cats totally separate at first, letting only one out at a time, since the apartment is new to both of them and moving stressed both of them out. Maggie hisses when she sees Blossom, which is normal for her to a new cat, but she generally likes other cats and has gotten along with every cat I've lived with previously just after a few days. Blossom can barely see, and has attacked my cat everytime we try to introduce them. We're not sure about Blossom's long-range hearing or sense of smell either. Maggie has never tried to attack or go after Blossom, and just seems absolutely terrified of her. Most of the time Blossom just chases Maggie into my room, stopping at the threshold and walking away.

Yesterday I had Maggie outside on her leash for her daily "walk", and when we came back to the screen door, Blossom was sitting at it, and they sat on either side and hissed at each other until they had calmed down and were just sitting there. I told my roommate to pick Blossom up so we could come inside and Blossom went berzerk and attacked my roommate. My roommate put her in her room for the rest of the day.

I know that moving is hard on cats, and Blossom is old, and we've beent trying to make this as easy as possible on both of them. But we think that Blossom is frightened by the fact that she can't see Maggie, and maybe can't hear or smell her that well, and we don't know what to do about it beyond what we've already done.

It's very possible that Blossom is just too set in her ways to even think about being friends with another cat. I would keep working with them slow, and she might come around.

Also to be safe, I would ask Blossom's owner to take the cat into the vet to be checked. Stress in older cats sometimes can turn into major health issues. Attacking and biting and scratching can also be a stimulus to pain.

You can try the vanilla extract tip- and put some on the underside of the chins of both cats as well as the base of their tail. I would put more than a drop or so, since the one cat has problems smelling.

But if I were in your situation, I would take Blossom to the vet and ask for a blood panel to be run.

I had already thought about asking my roommate to take Blossom to the vet. She seems to be fine though unless Maggie is around. Still, she should probably still be checked out.

I also thought that instead of vanilla to try Vicks Vapo-Rub. Why? Because Blossom is obsessed with the stuff. It is the weirdest thing I have ever seen. Blossom tolerates me in the same room, but that's about it. I went in her room and saw the jar and put a little on my hand and let her smell it and she came out and got all lovey and let me pet her. That's never happened before. Maybe if I put some on both of them it will calm Blossom enough to not freak out, and they will still smell the same. Especially if we keep a screen between them.

Another friend mentioned for me to get a baby gate at the flea market or a garage sale and put it up in my bedroom door. I am not sure about that because I think both cats would have no problem jumping it.