I had a cat, that was always in the house, recently we let the cat out doors. After a few weeks of going out, the cat started to slow down, it did not play, the cat seemed to rest all the time. It also stopped eating and drinking (my guess on the rate of food left behind). This is all hindsight now. But after a few weeks of sickness, I came home from a long trip and my wife said she had not see the cat for a few days. I found the cat dead. I felt so bad, because I should have taken it to a vet. I was thinking it must just be sick and will get over it. We have 3 other cats, but that was my favorite. After many pets and many years of having them, this is the first time one has gotten sick and died as a young cat. I wonder what would cause this? I don't think it was poison because that would not make the cat slow down for weeks and then die. It is a terrible feeling thinking I may have been able to help the poor thing.