Princess Isabella arrives at 18th birthday celebration at The Royal Danish Theatre in Copenhagen

Princess Isabella of Denmark has stunned the world overnight during her arrival at the second of two 18th birthday celebrations held in her honour.

Princess Isabella turns 18 on April 21 but her official celebrations were brought forward to avoid a clash with Easter Monday. She was pictured arriving at The Royal Danish Theatre in Copenhagen where a special performance was held in her honour.

Isabella had been expected to wear the Order of the Elephant insignia for the first time, but instead, she borrowed a pair of her mother’s diamond earrings for the occasion, which she paired with a black ball gown.

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She posed on the red carpet beside her proud parents, King Frederik and his Australian born wife of 20 years, Queen Mary, and their three other children, Prince Christian, 19, and twins Prince Vincent and Princess Josephine, 14.

Also there was Queen Margrethe, who abdicated just over a year ago in favour of her eldest son, as well as Isabella’s royal cousins Count Nikolai and Count Felix of Monpezat, who were stripped of their HRH and princely titles at the start of 2023.

Count Nikolai has been living in Australia since 2023, where he is attending university in Sydney, and is believed to have flown into Denmark just hours before the event.

They were joined by more than 1000 young people from across Denmark who were handpicked to attend the performance.

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Photos and videos of the big night were shared on the Danish Royal Family’s official Instagram page this morning, Australian-time.

“Tonight, young people from all over the kingdom are gathered in the heart of Copenhagen, where the Royal House and The Royal Theatre have jointly invited you to a special performance on the occasion of Her Royal Highness Princess Isabella’s 18th birthday,” an accompanying post said.

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“Over 1000 young people aged 17 to 24 years have gained a place among the audience at Gamle Scene through a lottery, where classic and modern features form the frame for a festive evening for the Princess and the youth.

“Youth took center stage as music, dance and theater filled the Royal Theatre in celebration of Her Royal Highness Princess Isabella’s 18th birthday.”

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The program included classical opera and ballet to modern dance, musicals and pop music performed by established Danish artists and young talents.

Princess Isabella will be presented with her Order of the Elephant Insignia when she turns 18, but some royal watchers expected her to wear it to the event.

It was also thought she may have worn one of the Danish royal family’s tiaras.

Instead, she wore her mother’s diamond fringe earrings, which were purchased at auction in 2016 and have been worn by Queen Mary on a number of occasions.

The Queen dazzled in a black top and silver skirt combination she has worn before, which she paired with pieces from the Danish royal collection known as the Queen Ingrid Ruby parure set, or Danish Ruby set. She opted to wear the earrings, necklace and brooch.

The concert marked the end of Princess Isabella’s official celebrations and came days after she cracked a joke during her first official speech at the April 11 party held in her honour at Aarhus City Hall.

She is expected to celebrate her April 21 birthday with a private party with her family.

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