What do you call a person who sits by grave and listens for bell to ring?

A person who sits by a grave and listens for a bell to ring is often referred to as a "graveyard watcher" or "grave watcher." Historically, this practice was associated with the fear of being buried alive, leading to the use of bells connected to a rope in graves, allowing those who were mistakenly buried to signal for help. Such individuals were also sometimes called "grave bell listeners." This practice has largely become obsolete with advancements in medical technology.