LONDON, UNITED KINGDOM - JUNE 30:  Catherine, Duchess of Cambridge arrives to board a plane of the Royal Canadian Air Force at London's Heathrow Airport on June 30, 2011 in London, England. The Duke and Duchess of Cambridge travel to Ottawa for their  first overseas tour as a married couple, the 11 day tour will take them to Canada and then on to California. (Photo by Steve Parsons - WPA Pool/Getty Images)