"MMMBop" is a song written and performed by the American pop rock band Hanson from their 1997 album Middle of Nowhere. In "Baby, You Knock Me Out", Cleveland Brown inadvertently sings it as part of the record-your-own-message birthday card he sent to Peter Griffin. Brown did not know how to turn the recording function off, and thus the card was still recording. As he sings it, Hanson's rendition plays on the radio, and doing so causes him to get pulled over.