AARHUS, DENMARK - APRIL 16: Crown Princess Mary and Princess Isabella of Denmark attend the 77th birthday celebrations of Danish Queen Margrethe at Marselisborg Palace on April 16, 2017 in Aarhus, Denmark. (Photo by Patrick van Katwijk/Getty Images)

AARHUS, DENMARK - APRIL 16: Crown Princess Mary and Princess Isabella of Denmark attend the 77th birthday celebrations of Danish Queen Margrethe at Marselisborg Palace on April 16, 2017 in Aarhus, Denmark. (Photo by Patrick van Katwijk/Getty Images)