CALGARY, AB - JULY 08: Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge arrive at Calgary International Airport for departure by Canadian Forces Airbus on July 8, 2011 in Calgary, Canada. (Photo by George Pimentel/WireImage)
CALGARY, AB - JULY 08: Catherine, Duchess of Cambridge visits the ENMAX Conservatory, Calgary Zoo on day 9 of the Royal couple's tour of North America on July 8, 2011 in Calgary, Canada. (Photo by George Pimentel/WireImage)
CALGARY, AB - JULY 08: Catherine, Duchess of Cambridge attends an official departure ceremony from Alberta and Canada on day 9 of the Royal couple's tour of North America on July 8, 2011 in Calgary, Canada. (Photo by Samir Hussein/WireImage)
CALGARY, AB - JULY 08: Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge visit the ENMAX Conservatory, Calgary Zoo on day 9 of the Royal couple's tour of North America on July 8, 2011 in Calgary, Canada. (Photo by George Pimentel/WireImage)
