ZWOLLE, NETHERLANDS - APRIL 27: Princess Laurentien of The Netherlands, Prince Constantijn of The Netherlands, Prince Floris of The Netherlands, Princess Marilene of The Netherlands and Prince Maurits of The Netherlands watch a demonstration by a piano player during King's Day (Koningsdag), the celebration of the birthday of the Dutch King, on April 27, 2016 in Zwolle, Netherlands. Parties and concerts are held across the Netherlands as members of the Dutch royal family oversee festivities. (Photo by Andreas Rentz/Getty Images)
