Sir David also met the rest of the Cambridge family, including Kate, Duchess of Cambridge and children Prince George, seven, Princess Charlotte, five, and Prince Louis, two.
And to mark the occasion, Sir David brought along a gift for Prince George with a special meaning.
Sir David decided to give George a giant shark tooth, which he found in Malta during a family holiday in the 1960s.
A tooth from the carcharocles megalodon species, the tooth is millions of years old and belongs to an animal which is now extinct.
