See Princess Mary of Denmark's Unusual Sign of Respect for Queen Margrethe

Crown Princess Mary has the utmost respect for her mother-in-law, Queen Margrethe — even if the gesture raises some eyebrows.

During a gala concert at Fredensborg Palace on Wednesday, Mary was seen pressing her back against a wall as the Queen entered the royal box in an apparent sign of respect. Queen Margrethe then took the middle seat of the front row, with Mary and Crown Prince Frederik sitting on either side of her to enjoy the musical performances.

“The music program offered a mix of Greenlandic, Faroe and Danish music culture, and along the way there was a common song ‘Now Thank All God,’ where the verses were sung alternating the three languages,” according the the Danish royals’ Instagram page.

The outing comes weeks after Princess Mary was named a regent, meaning she can perform duties as head of state when the Queen is unavailable.

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For the event, Princess Mary wore an elegant red dress featuring a keyhole neckline and long sleeves paired with silver heels, while Queen Margrethe opted for a forest green ensemble.