Animal Ghost
This isn't in the same league as some of your stories but years ago, when I was about eight, we had a siamese cat. Sheba only ever slept with me, no matter what.
When I turned ten Sheba was hit by a car and killed. It was, at the time, the worse thing that had ever happend to me. I didn't know how I was going to sleep without my Sheba.
Well, every night for the next six months after her death I swear Sheba came and slept at the end of my bed. Every night I'd get into bed and not long afterwards I'd feel something land on the end of the bed and settle down on my feet.
I have always believed Sheba came back to help me get over losing her. She must have decided, after the six months, that I was ready to move on. Sometimes, even now I miss feeling her on my feet, but I now have Hillie squashing my toes every night, maybe Sheba told her to!!