The yawn comes from The Twisted Tales of Felix the Cat, the 1990s animated revival of the classic cartoon cat, and appears in the episode Gross Ghost, released in December 1995. In that scene Felix is preparing for sleep, and the sleepy sound fits the character's playful cartoon style. Because the clip is short and easy to recognise as tiredness without any words, editors have reused it as a reaction sound for bedtime, exhaustion and winding down. Its charm comes from nostalgia for Felix and from how it signals that a day, stream or story has reached its end.