YPRES, BELGIUM - JULY 31:  Catherine, Duchess of Cambridge and Queen Mathilde of Belgium during a ceremony at the Commonwealth War Graves Commisions's Tyne Cot Cemetery on July 31, 2017 in Ypres, Belgium.  The commemorations mark the centenary of Passchendaele - The Third Battle of Ypres.  (Photo by Chris Jackson/Getty Images)