The phrase oopsy daisy has long been used in English as a gentle way to brush off a small slip or stumble, which makes it a natural setup for a prank fart sound. This particular clip is a short user-shared soundboard recording rather than a line from a film or show, and it has circulated mainly as a downloadable effect for memes and short videos. Its appeal is simple: the familiar, innocent phrase contrasts with the long, rude noise that follows, so creators keep reaching for it whenever they want a cheap, instantly recognisable gag.