'You're killing me, Smalls' comes from the 1993 film The Sandlot, where the line is said by Ham Porter. Over time, the quote spread far beyond the movie through memes, GIFs, reaction videos and short-form edits. It stayed popular because the wording is memorable and the delivery fits everyday moments of mild disbelief or teasing frustration. Online, people use it as a shorthand reaction when someone is overcomplicating something, missing the point or saying something embarrassingly obvious.