My father became very bonded with our Siamese cat, Victoria. After she crossed over the Rainbow Bridge, my father insisted that she would come and sleep with him at night; he would feel her jump up on the bed and walk around. This is surprising, since my father is the last person you would think would believe in anything paranormal. But knowing Victoria, it is undoubtly so; she loved him very much and probably didn't want to leave him.
I had a cat named BC who had a large tumor. The vet said there was no cure, but as long as she seemed happy to let her be. She seemed pretty well off until one day I came home from work and she was hiding under a chair upstairs. Then she came downstairs and fell over; she couldn't get up. I called the vet and made arrangements for her to be put to sleep. After I had done it, I felt very guilty and anxious; had I rushed it? Maybe she should have had more time. One night, I had a dream where I heard her little meow and felt her crawl on my lap and start to purr. I woke up suddenly - it had seemed very real. Then I knew that BC had really visited me! She had set my mind at ease that she was happy and that I had done the right thing and that she still loved me.