This quote comes from Doctor Who and is associated with the terrifying child character from the 2005 episode The Empty Child, later continued in The Doctor Dances. The repeated question became one of the most memorable creepy lines from the revived series and spread widely through fan clips, horror compilations and reaction edits. It still gets used because the phrase is simple, recognizable and disturbing even out of context, making it effective for both genuine horror posts and ironic meme edits.