Kate Middleton and Princess Charlotte Curtsy to King Charles in New Behind-the-Scenes Look at Coronation

Princess Charlotte is picking up on royal etiquette from mom Kate Middleton!

In a clip from the new BBC documentary Charles III: The Coronation Year, which is airing in full in the U.K. on Tuesday, and circulated on X, rehearsals are underway for King Charles and Queen Camilla's coronation. Prince William and Princess Kate brought their three children, Prince George, Princess Charlotte and Prince Louis, to the practice session at Westminster Abbey and were spotted greeting the King.

King Charles and Prince William, 41, said hello to each other first, kissing each other on both cheeks. The monarch, 75, then embraced his daughter-in-law, 41, with a hug and kiss before Princess Kate dipped into a quick curtsy.

King Charles then greeted his granddaughter Princess Charlotte, 8, in the same way, and Charlotte expertly followed protocol and also curtsied after their hug.

Prince George, 10, and Prince Louis, 5, also hugged their grandfather.

Prince William was also spotted brushing Prince George's hair off his forehead.

Richard Jackson, the Bishop of Hereford, said to the camera, "I think what struck me particularly is how extraordinarily affectionate they are. They're clearly a very close family, of all the generations, and in a sense, you felt you're part of a family occasion as well as, you know, a royal occasion and a national occasion."

Just as public citizens may opt to do when meeting a royal, it's common to see members of the family showing respect while greeting each other. Men traditionally bow their heads while women curtsy.

Following Queen Elizabeth's death last year, her eldest son immediately acceded to the throne as His Majesty King Charles alongside his wife, Her Majesty Queen Camilla. All members of the royal family, including those with His/Her Royal Highness (HRH) titles such as Princess Kate, bow or curtsy to the monarch and his wife when greeting them for the first time in a while — even his children!

When royals aren't seen bowing or curtsying to greet the King and Queen, there's usually a logical reason why: they may have already seen each other that day.

The documentary also captured intimate moments behind-the-scenes of the crowning ceremony, including King Charles poking fun at his "sausage fingers" as Prince William practices tying a robe on him and the staff at Buckingham Palace welcoming them back after the coronation service.

BBC described the film by saying, "With unrivaled insights from many of those involved, as well as moments of great poignancy and humor, this film gives a unique perspective on the inner workings behind a defining moment which marks a new era in the history of the monarchy."

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Kate Phillips, BBC Director of Unscripted, said: “It’s a real privilege to be given such extraordinary behind-the-scenes access to the first year of King Charles’ reign. It is a remarkable time in history, and this documentary will offer a unique insight into King Charles and Queen Camilla, and the preparation and planning leading to their coronation, a momentous ceremony watched by millions around the world.”

Princess Kate is a key member of the royal family, as was displayed when she recently helped King Charles and Queen Camilla host more than 500 members of the diplomatic corps at the annual Buckingham Palace reception on Dec. 5. The Princess of Wales worked the room, glittering in the historic Lover's Knot tiara. 

“She hugely enjoyed that evening and looked really at home,” a royal source tells PEOPLE exclusively in this week's issue. “She knows the important role the family plays in building relationships globally on behalf of the U.K.” Adds the insider: “It is clear that she and the King are quite close — in some respects closer to him than William."