For the past two weeks my 5 year old keeps saying "Grandma's dead" out of the blue. My mother is 67 but not gravely ill. What is going on?

He says it every couple of days, and nothing brings it on as far as I can tell. My mother is always nowhere around, he hasn't seen her that day or spoken to her. Yet suddenly he'll stop whatever he's doing, look at me and say "Grandma's dead", then go back to whatever he's been doing....

Ask him where he heard that- it could be from a cartoon (some are just awful these days, and NOT meant for children), or somewhere else. It's possible he is just repeating something he heard, and isn't connecting the meaning of it at all.