TILBURG, NETHERLANDS - APRIL 27: King Willem-Alexander, Queen Maxima, Princess Amalia, Princess Alexia and Princess Ariane attend the King's 50th birthday during the Kingsday celebrations on April 27, 2017 in Tilburg, Netherlands. (Photo by Patrick van Katwijk/Getty Images)
TILBURG, NETHERLANDS - APRIL 27: (L-R) Princess Ariane, King Willem-Alexander, Princess Amalia and Queen Maxima attend the King's 50th birthday during the Kingsday celebrations on April 27, 2017 in Tilburg, Netherlands. (Photo by Patrick van Katwijk/Getty Images)
Dutch King Willem Alexander hugs his daughter Amalia as the he celebrates his 50th birthday in Tilburg on April 27, 2017, as the Dutch celebrate King's Day. The king's 50th birthday happens to fall on King's Day or Koningsdag formally known as Queen' Day until King Willem-Alexander ascended to the throne in 2013 taking the reign from his mother. / AFP PHOTO / ANP / Koen van Weel / Netherlands OUT (Photo credit should read KOEN VAN WEEL/AFP/Getty Images)
TILBURG, NETHERLANDS - APRIL 27: Queen Maxima, King Willem-Alexander and their daughters Princess Amalia, Princess Alexia and Princess Ariane attend the King's 50th birthday during the Kingsday celebrations on April 27, 2017 in Tilburg, Netherlands. (Photo by Patrick van Katwijk/Getty Images)
