The Queen, Duke Of Edinburgh And Princess Alexandra Attend Reception At Canada House

LONDON, ENGLAND - APRIL 19: Prince Philip, Duke of Edinburgh (L), in his role as Colonel-in-Chief of The Royal Hamilton Light Infantry, signs the visitors' book as Queen Elizabeth II (R), Colonel-in-Chief of the Calgary Highlanders regiment, is greeted by Princess Alexandra (R), Colonel-in-Chief of the Canadian Scottish Regiment, ahead of a reception at Canada House at Canada House on April 19, 2015 in London, England. (Photo by Leon Neal - WPA Pool/Getty Images)