Charles, Prince of Wales (2nd R) poses for a family photo with Alexander (Aleksandar Karadjordjevic), Crown Prince of Yugoslavia (R), Crown Princess Katherine (3rd L) and her daughter Alison (L), Peter, Hereditary Prince of Yugoslavia (2nd L) at the Royal Palace in Belgrade on March 16, 2016. After visiting Croatia, Prince Charles and his wife arrived to a two-day visit to Serbia, part of a regional tour that will include Serbia, Montenegro and Kosovo. / AFP / ANDREJ ISAKOVIC (Photo credit should read ANDREJ ISAKOVIC/AFP/Getty Images)

Charles, Prince of Wales (2nd R) poses for a family photo with Alexander (Aleksandar Karadjordjevic), Crown Prince of Yugoslavia (R), Crown Princess Katherine (3rd L) and her daughter Alison (L), Peter, Hereditary Prince of Yugoslavia (2nd L) at the Royal Palace in Belgrade on March 16, 2016.
After visiting Croatia, Prince Charles and his wife arrived to a two-day visit to Serbia, part of a regional tour that will include Serbia, Montenegro and Kosovo.    / AFP / ANDREJ ISAKOVIC        (Photo credit should read ANDREJ ISAKOVIC/AFP/Getty Images)