Often the REM sleep behavior disorder is discovered not by the sleeper but by the partner, reports GoodTherapy.org.

Rona and Crandall have been married for many years. When they first got together, Rona learned Crandall had a history of talking in his sleep. He thought it was just a cool fact about himself, but Rona didn’t think it was cool at all—he scared her sometimes when he shouted and thrashed at invisible demons, but he usually calmed at her touch or the sound of her voice. Sleep talking is fairly common, and they lived with it.