AMSTERDAM, NETHERLANDS - SEPTEMBER 16: Prince Pieter-Christiaan of The Netherlands attend the 80th birthday celebration of Princess Irene in theater Carre on September 16, 2019 in Amsterdam, Netherlands. (Photo by Patrick van Katwijk/Getty Images)
AMSTERDAM, NETHERLANDS - SEPTEMBER 16: Prince Pieter-Christiaan of The Netherlands attend the 80th birthday celebration of Princess Irene in theater Carre on September 16, 2019 in Amsterdam, Netherlands. (Photo by Patrick van Katwijk/Getty Images)