Queen Elizabeth’s four children carried out a solemn tradition.

On Monday evening,King Charles III,Princess Anne,Prince AndrewandPrince Edwardcame together to conduct the Vigil of the Princes as their mother’s coffinlaid in stateat St. Giles' Cathedral in Edinburgh, Scotland. The siblings stepped out beside their mother’s casket, draped in the Royal Standard of Scotland and topped with afloral wreathand the Crown of Scotland.

For about 10 minutes, the royals joined the Royal Company of Archers, who will guard the Queen’s casket around the clock during its time in St. Giles, for a symbolic stand of guard as members of the public paid their respects. King Charles, sporting a Scottish kilt, took a spot of significance at the head of the coffin.

King Charles.JANE BARLOW/POOL/AFP/Getty

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The rare ritual has been performed only twice before in British history, first for the funerary processions for the Queen’s grandfather, King George V, in 1936, and again during the Queen Mother’s funeral events in 2002, according toThe Independent.

Vigil for King George V in 1936.The Print Collector/Print Collector/Getty Images

King George V lying in state in Westminster Hall, London, January 1936. The King’s four sons, the future King Edward VIII, the Duke of York (the future King George VI), Prince Henry, Duke of Gloucester and Prince George, Duke of Kent, mounted the guard at the catafalque on the night before the funeral as a mark of respect to their father.

Today’s Vigil of the Princes marks the second time that Charles, 73, Andrew, 62, and Edward, 58, have ceremoniously protected a casket as it laid in state. The brothers and their cousin David Armstrong Jones,Princess Margaret’s son, guarded the Queen Mother’s coffin for the same rite the day before her funeral 20 years ago.

Vigil for The Queen Mother in 2002.Pool Photo/Getty Images

Prince Charles of Britain stands in vigil at the coffin of his grandmother the Queen Mother as it lies in state April 8, 2002 in Westminster Hall, London

Princess Anne’s participation in the Vigil of the Princes was significant, as she became the first female royal to join the symbolic watch.

The Queen’s only daughter, 72, has had a visible role in her mother’s funeral events so far, fromfollowingthe coffin for the six-hour trip from Balmoral Castle to Edinburgh Sunday towalking with her brothersbehind the casket as it moved from the palace to St. Giles' on Monday.

The late monarch’s coffin will lie at the medieval cathedral overnight to allow staff members from the Palace of Holyroodhouse to pay their respects.

Princess Anne.Jane Barlow/AP/Shutterstock

Princess Anne and other members of the royal family hold a vigil at the coffin of Queen Elizabeth II

On Tuesday, the coffin will be flown to London, with Princess Anne again accompanying her mother’s body. Once the casket arrives at Buckingham Palace, a rehearsal will be held for its procession to the Palace of Westminster.

Astate funeralforQueen Elizabethis set to be held at Westminster Abbey on Monday, September 19.

source: people.com