Okay, so I have a cat named Celine and she's always been a bigger cat, since she got fixed anyway, she got up to probably 15-20lbs. The vets all said it was healthy and normal as long as she was active, which she was. We have three cats - Celine (who is I believe 12 years old) and two kittens who are almost a year old.

Celine used to love playing with the two kittens, but in the last two months she's lost weight drastically, as in she's probably 9lbs. soaking wet. Her fur is matting, she pants when she walks only 2 feet, and she has these 'seizure' type things where her back legs will tense up and we have to rub her thighs and stomach for about 20 min. before she can get up and walk again.

I've researched as much as I can, but I'm not finding a lot. Most sources say Feline Leukemia, but the sites also say that's contagious and the other kittens would've gotten it too - the kittens are perfectly healthy. One of which is gigantic and fat as a cow.

The only thing besides that I can think of is diabetes, or some kind of cancer of sorts. But I really don't know. She's even having trouble getting into the litter pans to go to the bathroom, and they're not very high off the ground. We're trying to get a lower to the ground litter pan for her, but we're worried that might not even be enough.

So, any advice guys? I know we need to take her to the vet - we are on Wednesday - so any advice besides that? Similar situations? I'm at a loss because this is a cat we've had for a really long time and I don't know what to do for her...

Go to the vet immediately before its too late! Get her catmilk so she get some food and stay alive (NOT normal milk, she will get more sick)

it can be anything, ranging from worms to something serious.

She still eats and drinks fine, that's not a big problem for her. It's just walking around and being active are getting to be a strain on her ): I've even brought food to her and water when she's having a hard time walking, and we got her softer food than the kittens so she can chew it and eat easier.

I'd have to say diabetes or thyroid problems. If you go to the vet I think they test for both.

I was gonna say Diabetes as a first guess, just by reading what she's going through. And Thyroid problems could definitely be the case, and I'm pretty sure that falls under the Endocrine system, or Endocrine disease.

She could also have a problem with her pancreas. And all three of these things I have mentioned belong to the Endocrine system..

The exact thing happened to my kitty :( He got really skinny and stopped grooming himself so his fur got matted up too. Then he would have seizures and stop moving around. When we took him to the vet, he ended up having leukemia and we had to put him down :( He was my cat and I loved him to death, but he was in so much pain so at least he's in a better place now.

:/ if he's suffering as such maybe you need to put him down. Keeping him alive would just keep him in this state of hurt.

Thank you guys for all the suggestions - and the only reason I think it's not leukemia is everywhere I've looked says that leukemia in cats is highly contagious, and none of my other cats have even shown signs. Granted they could just not be showing symptoms yet, it seems more likely (or at least Im hoping) to be a more minor and fixable problem...

If your cat cannot walk more than 2 feet without panting + the dramatic weight loss + seizures, it IS suffering.

Stop making excuses and take the fucking thing to the vet.

I had a cat that we put down over a year ago. She was a huge chunk of my life, I loved her. She however, was very sick and her life was cut short. She couldn't say, it hurts, I'm in pain, but you knew she was. Keeping her alive was forcing her to continue to walk around uncomfortable. She had differant symptoms than your cat, but they were fatal and painful. I agree with I read the list of things you said in your first post and went, that can't be good :/ Seizures are horrible, and if it's bad for a person, it's probably just as bad for an animal. she's also having matted fur? that could be a sign of potential weakness, if she can't properly groom herself, then she has given up a little. I know you love your cat but there are some things you just can't ignore.

And Ristina - I'm not ignoring anything. I'm taking her to the vet like I said several times now.

Having a mod lock since clearly you can't get GOOD advice here. You just get people who don't bother to read the first post and instead jump on you for everything you 'should be doing'.

Thanks to those who actually GAVE ME ADVICE AND IDEAS. I apprecaite it a lot.

Really guys, this got out of hand a long time ago.

locking at OPs request.