DUBLIN, IRELAND - MAY 18: (NO UK SALES FOR 28 DAYS) Queen Elizabeth II arrives for a State Dinner on May 18, 2011 in Dublin, Ireland. The Duke and Queen's visit to Ireland is the first by a monarch since 1911. (Photo by Samir Hussein/WireImage)
DUBLIN, IRELAND - MAY 18: (NO UK SALES FOR 28 DAYS) Queen Elizabeth II arrives for a State Dinner on May 18, 2011 in Dublin, Ireland. The Duke and Queen's visit to Ireland is the first by a monarch since 1911. (Photo by Samir Hussein/WireImage)