WARSAW, POLAND - JULY 17: Prince William, Duke of Cambridge, Catherine, Duchess of Cambridge and Poland's First Lady Agata Kornhauser-Duda attend the Queen's Birthday Garden Party at the Orangery, Lazienki Park on day 1 of their official visit to Poland on July 17, 2017 in Warsaw, Poland. (Photo by Julian Simmonds-Pool/Getty Images)
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WARSAW, POLAND - JULY 17: Prince William, Duke of Cambridge, Catherine, Duchess of Cambridge and Poland's First Lady Agata Kornhauser-Duda attend the Queen's Birthday Garden Party at the Orangery, Lazienki Park on day 1 of their official visit to Poland on July 17, 2017 in Warsaw, Poland. (Photo by Julian Simmonds-Pool/Getty Images)
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WARSAW, POLAND - JULY 17: Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge prepare to toast HM The Queen at the Queen's Birthday Garden Party at the Orangery, Lazienki Park on day 1 of their official visit to Poland on July 17, 2017 in Warsaw, Poland. (Photo by Julian Simmonds-Pool/Getty Images)
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WARSAW, POLAND - JULY 17: Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge toast HM The Queen at the Queen's Birthday Garden Party at the Orangery, Lazienki Park on day 1 of their official visit to Poland on July 17, 2017 in Warsaw, Poland. (Photo by Julian Simmonds-Pool/Getty Images)
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WARSAW, POLAND - JULY 17: Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge attend the Queen's Birthday Garden Party at the Orangery, Lazienki Park on day 1 of their official visit to Poland on July 17, 2017 in Warsaw, Poland. (Photo by Julian Simmonds-Pool/Getty Images)
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