QUEENSTOWN, NEW ZEALAND - APRIL 13: Catherine, Duchess of Cambridge stumbles as she walks through the vineyard with Prince William, Duke of Cambridge visit the Amisfield Winery on April 13, 2014 in Queenstown, New Zealand. 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 Arthur Edwards - Pool/Getty Images)