A few years ago I had a cat named Dolly. She was a pretty healthy cat, and then one day she became ill. My mother and I took Dolly to the vet to see what was wrong with her, and the vet took Dolly into a back room to check her over. My mother wanted to go back into the room so that the cat wouldn't freak out (since she was kind of old we worried about her having a heart attack or something if she got too freaked out), but the vet said no.
We waited in the waiting room for about 10 minutes, and then the vet came back out and told us that Dolly had died of cardiac arrest.
We put Dolly's body into her carrier, took him home, and buried her in the garden.
That night, I was in my room mourning for Dolly, my mother was up in her room, and my uncle (who was visiting) was in the living room. My other two cats were downstairs. I didn't own any other animals at the time, and there was no one else in the house. Anyway, all of a sudden, I heard something run very hard and very in the kitchen. Now with Dolly, she was the fastest of my three cats, and whenever I'd feed her she would always run very hard and very fast down the stairs to get to the cat food first. Whatever ran in the kitchen sounded exactly like Dolly. I guess I wasn't the only one who heard the noise, because I heard my mother yell "What's that?", and my uncle went to my bedroom and said "Russel, was that you?" I said "No!" Then he said "Sis, was that you?" My mother said "No, it wasn't!" Then I heard my uncle go, "Oh...okay..." and he went back to the living room to watch T.V.
The noise came back a week later when I was home alone. I was in the living room petting my two other cats who were cuddled up in the chair with me, and I heard whatever it was run down the stairs again. I quickly picked the cats up off of me and put them into the chair, and then I ran out to the terrace. There was nothing in the terrace. I would also hear little meows now and then when I was alone, and something would scratch at the back door. I would always check, and there would be nothing there. After a few weeks all of the strange noises stopped.