Crown Prince Frederik and Crown Princess Mary's lives will change on Sunday as the royal couple are proclaimed King and Queen of Denmark, following Queen Margrethe's abdication.
Frederik, 55, has been heir to the throne since the age of three and now that baton will pass to his and Mary's 18-year-old son, Prince Christian.
The teenager celebrated his milestone birthday with a lavish gala dinner last October and will assume the title of Crown Prince of Denmark on 14 January.
But what else do we know about Prince Christian and his younger siblings?
Read on to find out about Crown Prince Frederik and Crown Princess Mary's four children.
Prince Christian
The future Crown Prince was born Christian Valdemar Henri John on 15 October 2005 at Rigshospitalet in Copenhagen.
He was named Christian to continue the Danish royal tradition of monarchs naming their first-borns sons either Christian or Frederik.
Christian was baptised in January 2006 at the Christiansborg Palace Chapel and counts his paternal uncle Prince Joachim, Crown Prince Pavlos of Greece, Crown Prince Haakon and Crown Princess Mette-Marit of Norway and Crown Princess Victoria of Sweden among his godparents.
As well as being the first Danish royal to attend nursery school, he was also the first to attend a public state school, Tranegårdskolen, in Hellerup.
At the age of two, he carried out his first official engagement with his late grandfather Prince Henrik at Copenhagen Zoo.
Christian undertook his first official engagement when he attended the opening of a new elephant house at the Copenhagen Zoo with his grandfather, Prince Henrik in 2008.
In 2022, Prince Christian was pulled out of boarding school, Herlufscholm, after a damning documentary alleged a culture of bullying and violence at the institution.
He is now in the final year of his secondary education at Ordrup Gymnasium in Gentofte.
Queen Margrethe hosted a glittering white-tie gala dinner at Christiansborg Palace for her grandson Christian's 18th birthday last October, with foreign royals in attendance.
See the other heirs of Europe in the video below...
Princess Isabella
Frederik and Mary welcomed their daughter Isabella Henrietta Ingrid Margrethe at Rigshospitalet on 21 April 2007, making her the first girl born into the Danish royal family since the birth of her great aunt, Queen Anne-Marie of Greece, in 1946.
Frederik's first cousin, Princess Alexia of Greece and Denmark, and Queen Mathilde of Belgium were named as Princess Isabella's godmothers at her baptism.
Like her older brother Christian, Isabella attended Tranegårdskolen for the first stage of her education, before attending Ingrid Jespersens Gymnasieskole.
She enrolled at her father Frederik and her uncle Joachim's former school Øregård Gymnasium in Hellerup last August.
Prince Vincent and Princess Josephine
Frederik and Mary's twins celebrated their 13th birthday on Monday 8 January.
Vincent Frederik Minik Alexander was born 26 minutes before his sister Josephine Sophia Ivalo Mathilda at Rigshospitalet in 2011.
The twins were baptised in April 2011 at the chapel of the Church of Holmen. As the younger sibling, Josephine wore a christening gown found among her late great-grandmother Queen Ingrid's belongings, making her the first child of a future Danish monarch not to wear the family's traditional christening gown – which was worn by her twin brother.
Like their older siblings, Christian and Isabella, Vincent and Josephine began their education at Tranegårdskolen.
As of August 2023, Josephine began attending Kildegård Privatskole in Hellerup.