Some European heads of state have marked milestones in recent years, including Queen Margrethe of Denmark's Golden Jubilee in 2022, while King Carl XVI Gustaf of Sweden will also celebrate the 50th year of his reign this year.
But what about the next generation of royals who will one day rule? Which young royals currently attend school together and which one is in line to inherit the throne above his older sister?
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Here's everything you need to know about the European royal children.
Belgium
Current monarch: King Philippe
Heir: Princess Elisabeth, Duchess of Brabant
Queen Mathilde and King Philippe are parents to Princess Elisabeth, born in 2001, Prince Gabriel, born in 2003, Prince Emmanuel, born in 2005, and Princess Eleonore, born in 2008.
Eldest child and future queen, Princess Elisabeth, is currently studying history and politics at Oxford's Lincoln College.
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Denmark
Current monarch: Queen Margrethe
Heir: Crown Prince Frederik
Crown Prince Frederik and Crown Princess Mary have four children – Prince Christian, born in 2005, Princess Isabella, born in 2007, and twins Prince Vincent and Princess Josephine, born in 2011.
In June 2022, after finishing the first year of his higher education, it was confirmed that future king Prince Christian would no longer attend Danish boarding school, Herlufsholm, after a documentary alleged a culture of bullying and violence at the institution. Christian now attends public school, Ordrup Gymnasium.
Luxembourg
Current monarch: Grand Duke Henri
Heir: Prince Guillaume, Hereditary Grand Duke of Luxembourg
Prince Guillaume, Hereditary Grand Duke of Luxembourg, and his wife, Princess Stephanie, Hereditary Grand Duchess of Luxembourg, are expecting their second child in April.
The couple welcomed their first child, Prince Charles, in May 2020, who is second in the line of succession.
Monaco
Current monarch: Prince Albert
Heir: Prince Jacques
Prince Albert shares twins, Prince Jacques and Princess Gabriella, with his wife, Princess Charlene. The Monaco head of state and the former Olympic swimmer welcomed their children in December 2014.
Despite being two minutes older than her brother, Princess Gabriella is behind Prince Jacques in the line of succession, as the Monegasque throne is male-preference primogeniture.
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Princess Gabriella and Prince Jacques also have two half-siblings.
Albert fathered Jazmin Grace Grimaldi, born in 1992, with real estate agent Tamara Rotolo. She was confirmed as Prince Albert's daughter in 2006 when she was almost 16 years old. He had previously said he wanted to protect her identity until she was an adult.
He also confirmed he was the biological father of Alexandre Grimaldi-Coste, born in 2003, whose mother is Nicole Coste, a former Air France flight attendant from Togo, in May 2005, just before he was enthroned as Prince of Monaco.
Neither Jazmin nor Alexandre are in the line of succession to the Monegasque throne as their parents never married.
The Netherlands
Current monarch: King Willem-Alexander
Heir: Catharina-Amalia, Princess of Orange
King Willem-Alexander and Queen Maxima have three daughters – Princess Catharina-Amalia, Princess Alexia, and Princess Ariane, born in 2003, 2005 and 2007 respectively.
Future queen Princess Catharina-Amalia is currently carrying out her first official tour, travelling around the Caribbean with her parents.
Princess Alexia is studying at the United World College of the Atlantic (UWC) in Wales, following in her father's footsteps.
Norway
Current monarch: King Harald V
Heir: Crown Prince Haakon
Crown Prince Haakon and Crown Princess Mette-Marit are parents to Princess Ingrid-Alexandra and Prince Sverre Magnus, born in 2004 and 2005 respectively.
Princess Ingrid-Alexandra made her tiara debut last summer, just a few months after her 18th birthday.
Crown Princess Mette-Marit also has an older son, Marius Borg Høiby, from a previous relationship.
Sweden
Current monarch: King Carl XVI Gustaf
Heir: Crown Princess Victoria
Crown Princess Victoria and her husband, Prince Daniel, share two children – Princess Estelle and Prince Oscar, who were born in 2012 and 2016 respectively.
Spain
Current monarch: King Felipe
Heir: Leonor, Princess of Asturias
King Felipe and Queen Letizia have two daughters – Princess Leonor and Infanta Sofia, who arrived in 2005 and 2007 respectively.
Princess Leonor is currently a student at UWC in Wales, alongside the Netherlands' Princess Alexia.
Meanwhile, Infanta Sofia currently attends the Santa María de los Rosales school in Madrid.
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