SYDNEY, AUSTRALIA - APRIL 16:  Prince William, Duke of Cambridge, Prince George of Cambridge and Catherine, Duchess of Cambridge arrive at Sydney Airport on a Australian Airforce 737 aircraft on April 16, 2014 in Sydney, Australia. The Duke and Duchess of Cambridge are on a three-week tour of Australia and New Zealand, the first official trip overseas with their son, Prince George of Cambridge.  (Photo by Chris Jackson/Getty Images)