The Next Queen Elisabeth (of Belgium!) Celebrates 21st Birthday with Stunning New Portraits

HAND OUT BELGIAN ROYAL PALACE -/BELGA MAG/AFP via Getty

Happy birthday, Princess Elisabeth of Belgium!

The heir to the Belgian throne turned 21 on Tuesday, and the palace released two gorgeous portraits to celebrate the occasion.

"Princess Elisabeth is celebrating her 21st birthday today! Happy Birthday!" the Belgian Royal Palace wrote on Twitter, sharing two shots of the royal looking out a window in an off-the-shoulder white top and statement gold earrings.

Elisabeth is currently enrolled at Oxford University in Oxford, England, completing a three-year course in history and politics at Lincoln College, the palace announced when she began her studies last fall. The future Queen previously earned her International Baccalaureate from the United World College of the Atlantic in Wales in 2020 and spent a year at the Royal Military Academy in Brussels.

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When officials announced that Princess Elisabeth would study at Oxford, it was emphasized that she would frequently travel back to her home country to stay connected.

"The Princess will return to Belgium regularly and remain involved in Belgian public life," the statement said.

The eldest child of King Philippe and Queen Mathilde, Elisabeth became heir apparent to the Belgian throne in 2013 following the abdication of her grandfather, King Albert II.

Laurie Dieffembacq - Royal Belgium Pool/Getty Princess Elisabeth

When she eventually becomes monarch as expected, she will become Belgium's first Queen regnant. A new act of succession which introduced absolute primogeniture in the country was put into effect in 1991, 10 years before her birth.

As Princess Elisabeth celebrates her milestone birthday, royal duty has called her parents abroad. King Philippe, 62, and Queen Mathilde, 49, are currently in Lithuania for a three-day state visit, celebrating 100 years of diplomatic relations between the two nations.

POOL DIRK WAEM/BELGA MAG/AFP via Getty

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On their first day, Queen Mathilde visited the Vilna Gaon Museum of Jewish History with First Lady Diana Nausėdienė while King Phillippe laid a wreath at Antakalnis cemetery, honoring those who lost their lives in the fight for Lithuanian independence.

The day wrapped with a glamorous state dinner at the Grand Presidential Palace of Vilnius. The King was dapper in a tux, while the Queen popped in a red cape gown with a blue floral print. Mathilde shimmered in a delicate tiara, sparkling as Elisabeth did for her first tiara moment over the summer.

Dirk Waem-Royal Belgium Pool/Getty

In June, royals from around the world gathered to celebrate the 18th birthday of Princess Ingrid Alexandra of Norway with a grand gala. There, a significant picture was taken of four future Queens — including the birthday girl.

Princess Ingrid Alexandra took the center spot in a purple dress and the Boucheron Circlet Pearl Tiara, which originally belonged to her great-great-grandmother Princess Ingeborg of Sweden.

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LISE ASERUD/NTB/AFP via Getty Front (L to R): Princess Estelle, Princess Ingrid Alexandra, Prince Charles. Back (L to R) Princess Catharina-Amalia and Princess Elisabeth

Standing in the back row were Princess Catharina-Amalia of the Netherlands, 18, Princess Elisabeth, while Princess Estelle of Sweden, 10, and Prince Charles of Luxembourg, 2, sat up front.

While Princess Estelle sported a floral headband that matched her blue dress for the photo op, the other princesses sported tiaras — for the first time ever! Princess Catharina-Amalia shined in the Dutch Star Tiara, while Princess Elisabeth debuted a sparkler that had never previously been seen.