Tiara Alert! Prince Christian of Denmark's 18th Birthday Gala Invites Reveal Luxe Dress Code

All about why his sister, Princess Isabella, might sport a tiara for the first time

Preparations are underway for Prince Christian of Denmark’s 18th birthday bash!

On Thursday, the Danish Royal House posted an upbeat Instagram video of palace staffers mailing invitations for the prince’s birthday gala in October. Fan blog Gert’s Royals noted on X that invites stipulated a formal dress code, which hints at tiara wear for Christian’s mother Crown Princess Mary, his grandmother Queen Margrethe and more.

"The invitations say the dress code is: Galla B (B meaning Ballgown)/Uniforms/ White tie/ Gowns Decorations (Honors) and Tiaras may be worn," Gert’s Royals wrote, translating from Danish.

The Instagram video showed courtiers printing and packing the cards, which were printed in script below a royal court of arms, in the Court Marshal's Secretariat and stamped in the Royal Palace's post office in the Yellow Palace.

Related: Princess Maria Chiara of Bourbon Two Sicilies Responds to Prince Christian Relationship Rumors

“Then there is mail! 💌 📪,” the caption began. “Several hundred invitations were sent out from Amalienborg today. The recipients are the many guests who have been invited to Her Majesty the Queen's gala dinner on the occasion of His Royal Highness Prince Christian's 18th birthday on 15 October.”

Prince Christian is the eldest son of Crown Prince Frederik and Crown Princess Mary, making him second in line to the Danish throne. He is followed in the country’s line of succession by his younger siblings — Princess Isabella, 16, and 12-year-old twins Prince Vincent and Princess Josephine.

While Christian focuses on school and steps out with his family for major royal occasions, it was announced over the summer that his upcoming birthday would be celebrated with two events held one month apart, serving as a more formal step into the royal spotlight. The Danish Royal House shared the official plans in August along with three new portraits of the future king.

"On Sunday 15 October 2023, His Royal Highness Prince Christian turns 18. Authority Day is celebrated with a changing of the guard at Amalienborg, where the Prince, together with his family and Her Majesty the Queen, appear on the balcony of Frederik VIII's Palace. In the evening, the Queen hosts a gala dinner where the guests reflect Prince Christian's own generation," the Danish Royal House said in a statement.

The gala that evening at Christiansborg Castle will welcome reps from some of Denmark’s youth organizations plus young people “who have distinguished themselves in the world of sport, art and culture.”

Extending the guest list, the Royal Palace will work with local municipalities to coordinate invitations for around 200 young people from the Danish Commonwealth, allowing each of Denmark’s municipalities, Greenland and the Faroe Islands to invite two 18-year-old guests to the party.

Related: Meet Denmark's Royals: Your Guide to the Danish Monarchy's Family Tree

The festivities continue one month later and take a more formal turn. On Nov. 14, Prince Christian will attend a meeting of the Council of State (which is comprised of government ministers) and declare that he wishes to comply with the Danish constitution.

“Prince Christian will then be able to be appointed as head of state. Prince Christian will not get a seat in the Council of State until a change of throne has taken place,” the Danish Royal House said of the important step.

Prince Christian had his last white-tie moment in September 2022 for a celebration commemorating the 50th anniversary of Queen Margrethe’s accession. Christian opted for a classic tux, while his father Crown Prince Frederik, 54, wore a military uniform with regalia. Crown Princess Mary, 51, sparkled in a tiara and blush gown, while Princess Isabella popped in a bright red gown with her hair in a high ponytail.

Christian’s upcoming birthday bash could also mark a banner fashion statement for his younger sister — perhaps her first tiara wear!

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In a fashion clue, a June 2022 gala for Princess Ingrid Alexandra of Norway's 18th birthday gathered royals from around the world to celebrate. Three other future queens and a future grand duke — Princess Catharina-Amalia of the Netherlands, Princess Elisabeth of Belgium, Princess Estelle of Sweden and Prince Charles of Luxembourg — posed with the birthday girl for a regal portrait.

The event doubled as the tiara debut for Princess Catharina-Amalia and Princess Elisabeth, adding to the chances that Princess Isabella might sport a sparkler at her brother’s big party.

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