Queen Elizabeth II and South African President Jacob Zuma enjoy a toast at the start of the State Banquet at Buckingham Palace during the State Visit of South African President Jacob Zuma.   (Photo by Lewis Whyld/PA Images via Getty Images)
OLAND, SWEDEN - JULY 14:   Crown Princess Victoria of Sweden, Prince Oscar of Sweden, Princess Estelle of Sweden and Prince Daniel of Sweden arrives for Birthday celebrations of Crown Princess Victoria of Sweden at Solliden Palace on July 14, 2016 in Oland, Sweden. (Photo by Luca Teuchmann/WireImage)
Queen Sonja and King Harald of Norway arrive for a gala dinner at the Royal Palace in Oslo, Norway on May 9, 2017 to mark the 80th Birthday of the King and Queen.  

 / AFP PHOTO / POOL / Haakon Mosvold Larsen        (Photo credit should read HAAKON MOSVOLD LARSEN/AFP/Getty Images)
DUESSELDORF, GERMANY - AUGUST 23:  Prince William, Duke of Cambridge and German Chancellor Angela Merkel attend the celebrations of the 70th anniversary of North Rhine-Westphalia on August 23, 2016 in Duesseldorf, Germany. North Rhine-Westfalia was founded by the British military administration 70 years ago today.  (Photo by Andreas Rentz/Getty Images)
LONDON, ENGLAND - JULY 01:  A groundsman paints the white lines and another uses a mop on the grass as a cleaner works in the royal box on Centre Court at the Wimbledon Lawn Tennis Championships on July 1, 2013 in London, England. The 2013 Championships are entering their second week at the end of which  Centre Court will become the centre of the world's attention for the women's singles and men's singles finals.  (Photo by Peter Macdiarmid/Getty Images)