STIRLING, SCOTLAND - OCTOBER 24: Prince William, Duke of Cambridge during a visit to Stirling Castle on October 24, 2016 in Stirling, Scotland.  The Duke of Cambridge in his role as Earl of Strathearn is Patron of The Thin Red Line Appeal to redevelop The Argyll and Sutherland Highlanders Regimental Museum at the Castle.  (Photo by Mark Runnacles/Getty Images)