Denmark's Royal Twins Celebrate Birthday Before Grandmother Queen Margrethe's Shocking Abdication Next Week

Prince Vincent and Princess Josephine will move up in the line of succession when their father becomes King Frederik

Prince Vincent and Princess Josephine of Denmark are celebrating another birthday together.

Denmark's royal twins turned 13 on Monday, and the palace marked the occasion by sharing a new photo of the brother and sister.

"Their Royal Highnesses Prince Vincent and Princess Josephine have a birthday and are 13 years old today," they captioned the portrait by photographer Dennis Stenild of the pair.

The new image seems to be from October when the family celebrated Prince Christian's 18th birthday with a balcony appearance at Amalienborg Palace. Prince Vincent is wearing the same suit with a blue tie, while Princess Josephine is perfectly coordinating in a blazer over a similarly colored top for their big brother's milestone.

Related: Why the New King Frederik and Queen Mary of Denmark Won't Have a Coronation Like King Charles

Prince Vincent and Princess Josephine's big day comes just a week before their grandmother Queen Margrethe will abdicate the throne on Jan. 14. This will move both twins up in the line of succession to the throne — Prince Vincent, who is a few minutes older than his twin sister, will go from fourth to third, while Princess Josephine will get bumped up from fifth to the fourth spot.

Crown Prince Frederik and Crown Princess Mary, Vincent and Josephine's parents, will become the new king and queen. Queen Margrethe's eldest son will become King Frederik X, while his wife will be known as Queen Mary.

Ahead of Prince Vincent and Princess Josephine in the line of succession will remain their older siblings. Prince Christian will become Crown Prince Christian as the new heir, while Princess Isabella, 16, will be in the second spot behind her older brother.

Unlike the British, who marked King Charles' accession to the throne with an elaborate coronation ceremony in May 2023, the soon-to-be King Frederik, 55, and Queen Mary, 51, will not be crowned in a coronation service. Instead, a proclamation of the new reign will be made at Christiansborg Palace on Jan. 14. According to Royal Central, the prime minister has proclaimed each new monarch on the balcony of the Danish palace since the early 1900s.

Queen Margrethe, 83, was announced as monarch in a similar proclamation on Jan. 14, 1972, following the death of her father, King Frederik IX. This month's change of reign will come on the 52nd anniversary of her accession. But since Queen Margrethe abdicated and the change of reign didn't come as a result of a death, it will be a much happier occasion.

Queen Margrethe's abdication came as a surprise, as she previously said she would rule for her entire life and the last Danish monarch's abdication was in 1146, according to The Guardian.

Queen Margrethe, who became Europe's only female monarch following the death of the U.K.'s Queen Elizabeth in Sept. 2022, cited health concerns in her New Year's speech where she announced her abdication.

"In February this year, I underwent extensive back surgery. Everything went well, thanks to the competent health personnel, who took care of me. Inevitably, the operation gave cause to thoughts about the future – whether now would be an appropriate time to pass on the responsibility to the next generation," she said, per an English translation of the official speech transcription. "I have decided that now is the right time. On 14 January 2024, 52 years after I succeeded my beloved father, I will step down as Queen of Denmark. I leave the throne to my son Crown Prince Frederik."

Related: Crown Princess Mary of Denmark Will Have a Historic Royal First When She Becomes Queen This Month

There is speculation that the unexpected move came to bolster Crown Prince Frederik and Crown Princess Mary’s bond amid gossip of an affair. In November 2023, reports swirled that Frederik was having an affair with Mexican-born socialite Geneveva Casanova after they were photographed together in Madrid. Casanova denied allegations of a romantic relationship with Frederik, and the royal couple continued to display a united front in recent months.

Crown Princess Mary will also make history when she is declared as Queen mary, becoming the first queen consort born in Australia.

Born Mary Donaldson, the soon-to-be Danish queen was an Australian advertising executive before a chance encounter changed her life. She found herself chatting to Prince Frederik, although he introduced himself simply as "Fred," at the Slip Inn on Sydney's Darling Harbor in September 2000. The pub was filled with people from around the world who were in town for the Olympics.

Shortly into their conversation, Mary found out that she was talking to the Crown Prince of Denmark, heir to the 1,000-year-old Danish throne.

"The first time we met, we shook hands," she said of their introduction. "I didn't know he was the prince of Denmark. Half an hour later, someone came up to me and said, 'Do you know who these people are?' "

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For a year, the pair got to know each other through a long-distance relationship that flew under the radar of the media.

In 2002, Mary moved to Copenhagen, converted to the Lutheran Church and learned Danish, a notoriously tricky language to master. The couple announced their engagement in 2003 and married the following year at Copenhagen Cathedral.

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