2 Cat Conflict

Have your cats been checked by your veterinarian? This could be a health issue, not a behavioral one.

I would try isolating this kitty in a room by herself with her own litter box to see if you can get her to use a separate box. Then if successful, proceed from there. She at least needs to be in a room where there is no carpet on the floor.

Cats are very good at hiding their illnesses. Some cats tend to be more aggressive when they sense another is not well. Also, another reason for not using the litterbox is UTI or urinary tract infection.

Any time a cat pees out of the litter box it should raise a red flag. to be on the safe side it will not hurt to have a urinalysis done, she could be blaming the other box for her pain if its hurting her when she pees.

Believe me, I thought my cat madison was behavioral about his peeing until the day he peed blood. His timing always seemed to be when he was frustrated or I had played with the dog more, but it turned out he has struvite and oxalite crystals, had a uti and a couple weeks later, ended up in a life or death situation because he had developed a urethral blockage. that wa a $300 3 day stay at the vets office, and I know I could have prevented it sooner if I had just gone ahead and had the urinalysis done, even though I didn't think there was a medical issue.

further, I would like to hope that your first statement about letting her lose or having her PTS was a joke, if its that dire of a situation please re-home the cat instead of terminating her life for a mild inconvenience.

Even if you were just kidding, I don't appreciate people joking about that stuff. Putting a cat to sleep is a very serious thing. It's only been about 3 weeks since I HAD to put my 15 year old cat to sleep because he was dying and having to do it nearly killed me. I raised him from a little baby and he's the closest being I've ever had to lose in death. I miss him more than I've ever missed anyone who has left my life and I don't think I'll ever stop hurting over losing him. When people are so flippant about something that is so very serious, it really makes me angry.

And if you were not kidding then you don't belong with cats. Get a fish or something.

IMHO: After medical issues are ruled out and all the pee spots are treated with enzymatic cleaners (to discourage kitty from peeing there again), you may need to add another litter box (or 2 - ideally there should be 1 litter box per cat plus an extra and they should be cleaned 2x a day. Are the litter boxes kept clean?) and work on reintroducing your kitties - getting positive scent associations with eachother, using Feliway diffusers, etc. If you need links for articles ask - there's some good articles here about rintroducing kitties. Good luck.

Hope you can figure it out! No major advice from me though

When we spayed our younger cat, our older suddenly became very agressive towards her...lots of hissing and growling and fighting. I'm not sure what the issue was but they managed to sort it out themselves after a few weeks

I haven't ever had to use an enzymatic cleaner but from what I've read, they're not all created equal. A lot of people on this forum swear by Nok-Out which must be ordered online. (Maybe someone else can chime in about that.) With such good noses, the kitty may still smell that pee/poop thus continuing to use the rug. Maybe put a litter box in your room for now and remove the rug until the fear/stress is resolved?

Here's some info about Feliway:
http://www.feliway.com/us/Frequently-Asked-Questions
Please keep in mind that it is quite expensive at a store but basically half price on Amazon. I have been using Feliway the past several months - currently working on socializing a feral.

The kitty may not recognize the cat after the spay due to a change in scent from vet's office. You may want to try dabbing a bit of vanilla extract under their chins and at the base of their tail on their back - that will make them all smell the same. Search for 'vanilla extract' on the forums and you will find threads that explain that better. This thread about cat introductions will have a lot of relevant information that can help in that regards, with scent swapping, etc, in case there is an issue:

http://www.thecatsite.com/forums/showthread.php?t=67321

Here's a great article about inappropriate peeing:
http://www.thecatsite.com/forums/sho...&threadid=9563

Another thought is just making sure there's enough vertical space/hiding areas so there are other options to flea to other than your room. Kitty must feel safe and have a potty area easily accessible in safe areas. If kitty is too scared to venture out to use litter box in basement, that would make sense to use litter box in safe bedroom hiding place. So hopefully things like the cat re-intros/Feliway/more litter boxes/more hidey places/vertical space will help.

Please don't give up on your kitty. Many people have gone through this before and will be able to help you out.

You're very welcome! Please keep us posted and ask any questions along the way. Hopefully some of these adjustments will really help out your fur family.