LONDON, ENGLAND - JUNE 10: Queen Elizabeth II and Prince Philip, Duke of Edinburgh attend the service of thanksgiving for Queen Elizabeth II's 90th birthday at St Paul's cathedral on June 10, 2016 in London, United Kingdom. (Photo by Ian Vogler - WPA Pool/Getty Images)
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LONDON, ENGLAND - JUNE 10: Queen Elizabeth II and Prince Philip, Duke of Edinburgh attend the service of thanksgiving for Queen Elizabeth II's 90th birthday at St Paul's cathedral on June 10, 2016 in London, United Kingdom. (Photo by Ian Vogler - WPA Pool/Getty Images)
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LONDON, ENGLAND - JUNE 10: (L-R) Prince Edward, Earl of Wessex, Prince Harry, Catherine, Duchess of Cambridge, Prince William, Duke of Cambridge, Camilla, Duchess of Cornwall, Prince Charles, Prince Philip, Duke of Edinburgh and Queen Elizabeth II attend a service of thanksgiving for Queen Elizabeth II's 90th birthday at St Paul's cathedral on June 10, 2016 in London, United Kingdom. (Photo by Matt Dunham - WPA Pool/Getty Images)
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LONDON, ENGLAND - JUNE 10: (L-R) Prince Andrew, Duke of York, Princess Beatrice, Princess Eugenie, Princess Anne, Princess Royal, Sir Timothy Lawrence, Peter Phillips, Autumn Phillips, Zara Phillips and Mike Tindall sing during the service of thanksgiving for Queen Elizabeth II's 90th birthday at St Paul's cathedral on June 10, 2016 in London, United Kingdom. (Photo by Ian Vogler - WPA Pool/Getty Images)
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