BERLIN, GERMANY - JULY 21: Catherine, Duchess of Cambridge, and Prince William, Duke of Cambridge (R), ride an escalator as they arrive at Berlin Hauptbahnhof main railway station before taking a train to Hamburg on the third day of the royal visit to Germany on July 21, 2017 in Berlin, Germany. The royal couple are on a three-day trip to Germany that includes visits to Berlin, Hamburg and Heidelberg. (Photo by Sean Gallup/Getty Images)
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BERLIN, GERMANY - JULY 21: Catherine, Duchess of Cambridge, and Prince William, Duke of Cambridge (not pictured), arrive at Berlin Hauptbahnhof main railway station before taking a train to Hamburg on the third day of the royal visit to Germany on July 21, 2017 in Berlin, Germany. The royal couple are on a three-day trip to Germany that includes visits to Berlin, Hamburg and Heidelberg. (Photo by Sean Gallup/Getty Images)
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BERLIN, GERMANY - JULY 21: Catherine, Duchess of Cambridge, prepares to board a train for Hamburg at Berlin Hauptbahnhof main railway station on the third day of the royal visit to Germany on July 21, 2017 in Berlin, Germany. The royal couple are on a three-day trip to Germany that includes visits to Berlin, Hamburg and Heidelberg. (Photo by Matthias Nareyek/Getty Images)
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BERLIN, GERMANY - JULY 21: Catherine, Duchess of Cambridge, and Prince William, Duke of Cambridge (not pictured), arrive at Berlin Hauptbahnhof main railway station before taking a train to Hamburg on the third day of the royal visit to Germany on July 21, 2017 in Berlin, Germany. The royal couple are on a three-day trip to Germany that includes visits to Berlin, Hamburg and Heidelberg. (Photo by Sean Gallup/Getty Images)
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Getty Images Entertainment Sean Gallup