Possible Clues:

• Kid's retort
• Juvenile rebuttal
• 'Am not!' reply
• Joe Cocker's "You ___ Beautiful"
• ''You ___ Beautiful'' (Joe Cocker hit)
• ''Am not!'' rejoinder
• "You __ Beautiful": Joe Cocker hit
• "You --- right!"
• Schoolyard rebuttal
• Response to ''Am not!''