OSLO, NORWAY - MAY 10: Prince Nikolaos and Princess Tatiana of Greece arrive at the Opera House on the ocassion of the celebration of King Harald and Queen Sonja of Norway 80th birthdays on May 10, 2017 in Oslo, Norway. (Photo by Patrick van Katwijk/Getty Images)
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Getty Images Entertainment Patrick van Katwijk

OSLO, NORWAY - MAY 10: Prince Nikolaos and Princess Tatiana of Greece are seen arriving at the Opera House on the occasion of the celebration of King Harald and Queen Sonja of Norway 80th birthdays on May 10, 2017 in Oslo, Norway. (Photo by Rune Hellestad - Corbis/Corbis via Getty Images)
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OSLO, NORWAY - MAY 10: Prince Nikolaos, Greece and Princess Tatiana, Greece arrives at the Opera House on the occasion of the celebration of King Harald and Queen Sonja of Norway 80th birthdays on May 10 2017 in Oslo, Norway. (Photo by Nigel Waldron/ Getty Images)
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Getty Images Entertainment Nigel Waldron