The Duke And Duchess Of Cambridge Attend The St Patrick's Day Parade At Mons Barracks, Aldershot [Getty Images]

ALDERSHOT, ENGLAND - MARCH 17: Prince William, Duke of Cambridge drinks a pint of Guinness during the St Patrick's Day parade at Mons Barracks on March 17, 2014 in Aldershot, England. Catherine, Duchess of Cambridge and Prince William, Duke of Cambridge visited the 1st Battalion Irish Guards to present the traditional sprigs of Shamrocks to the Officers and Guardsmen of the Regiment. (Photo by Bradley Page - WPA Pool/Getty Images)

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