Hi, Welcome to JustAnswer. I'm a licensed veterinarian and I'll be happy to help. I'm sorry to hear that your little girl is sick. It would be the safest to take her to a vet now. There are several diseases that can lead to weight loss and increased water consumption and urine production. The two most serious diseases would be a complicated (quite sick) diabetic, and kidney disease. If she has one of these, then diagnosing her and beginning the appropriate treatment today would be very helpful for her.
hi, thank you for asking. unfortunatly my little Izzy had to be put down so am missing her a lot . the main thing was that she was happy and content right up until the end and she was loved.
thanks again for asking