Kermit the Frog and Miss Piggy have recorded a message for the Duke and Duchess of Cambridge to congratulate them on the birth of their son.
The royal baby was born on Monday at 4.24pm and is third in line to the throne.
An easel has been placed in the grounds of Buckingham Palace listing details of the birth.
The presentation of a note, confirming the gender of the child, has been a long-standing tradition for royal births.
He hasn't been named yet.
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