LUXEMBOURG - JUNE 23: Grand Duke Henri of Luxembourg and Prince Guillaume of Luxembourg during the Military parade for celebration of National Day 2 at Philarmonie on June 23, 2016 in Luxembourg, Luxembourg. (Photo by Sylvain Lefevre/Getty Images)
LUXEMBOURG - JUNE 23: Grand Duke Henri of Luxembourg and Prince Guillaume of Luxembourg during the Military parade for celebration of National Day 2 at Philarmonie on June 23, 2016 in Luxembourg, Luxembourg. (Photo by Sylvain Lefevre/Getty Images)