Help my sweet little FuzzyWuzzy Overcome Her Health Struggle

A sweet (sometimes fussy) little stray tabby showed up on my doorstep about 3 years ago. I provided her with food, water, and shelter on my front porch until this last month when I finally decided to bring her inside with my other male cats. I had the vet run every test possible to make sure she didn't have any communicable diseases and everything came back great. $695 bill.

She and my boys were adjusting very well... she's tiny but fierce and quickly let my boys, who are much larger, know that she wasn't going to be bullied! Then, all of a sudden 2 weeks ago, I noticed she was peeing everywhere! Or at least she was trying...and of course it was Friday night after my vet was closed. Off to the emergency vet we go! The vet diagnosed her with UTI, gave her pain meds and a shot of antibiotics. She said FuzzyWuzzy had a LOT of blood and crystals in her urine but was not obstructed and hopefully would be ok. My youngest male cat, Blackjack, nearly died from a kidney stone that completely occluded his urethra a few years ago. Therefore, both my males have been on prescription food to prevent stones ever since. I started FuzzyWuzzy on the same food (which is not cheap). After 2 days she was back to normal. Then, a week ago, she started peeing everywhere and actually passed a small stone and all was well again. Tonight she is peeing blood. I'm terribly afraid she may have Cancer. I am monitoring her closely tonight and if needed will take her to the emergency hospital. At any rate, I will take her to my vet as soon as they open in the morning.

I have already spent $1000 in 1 month and though I've never had a gofundme before I am afraid I may need some help. I want to do everything possible for this sweet baby who chose me to be her human. If you can help at all it will be greatly appreciated.