I heard a story on a cat which lived in a aged home. ( Those homes you go to when your about dead?) He used to lay on the end of the bed of someone and within 24 hours they died. He only ever lay next to people when they were near death.. I think he was comforting them. So the staff knew when he picked a bed to contact the family.
I may have the exact details wrong but thats the gist of the story