(L-R) Britain's Princess Eugenie of York, Britain's Princess Beatrice of York and Britain's Prince Andrew, Duke of York leave Buckingham Palace to meet guests at the Patron's Lunch, a special street party outside Buckingham Palace in London on June 12, 2016, as part of the three day celebrations for Queen Elizabeth II's official 90th birthday.
Up to 10,000 people are expected to attend the Patron's Lunch along with the monarch, her husband Prince Philip, Prince William and Prince Harry.
 / AFP / JUSTIN TALLIS        (Photo credit should read JUSTIN TALLIS/AFP/Getty Images)