Place this clip at the reveal moment in a birthday edit, after the build-up and before the reaction. Follow it with a scream meme sound button for extra chaos, then close with a yaaaay cheer sound button while gifts appear on screen.
About this sound
This clip is a person screaming the words to Happy Birthday to You instead of singing them, stretching the familiar tune over about eight seconds at full volume. It feels funny and jarring, turning a sweet, predictable greeting into an over-the-top surprise that catches everyone off guard.