EDINBURGH, UNITED KINGDOM - JULY 07: (EMBARGOED FOR PUBLICATION IN UK NEWSPAPERS UNTIL 48 HOURS AFTER CREATE DATE AND TIME) Queen Elizabeth II, Prince Philip, Duke of Edinburgh, Prince William, Duke of Cambridge and Princess Anne, The Princess Royal attend the Thistle Service at St Giles' Cathedral on July 7, 2016 in Edinburgh, Scotland. The Most Ancient and Most Noble Order of the Thistle is an order of chivalry associated with Scotland. (Photo by Max Mumby/Indigo/Getty Images)