Queen Elizabeth is ushering in the new decade with her three male heirs by her side.

Prince George, 6, Prince William, 37, and Prince Charles, 71, joined the monarch for the historic new portrait, which was taken just before the Queen’s annual Christmas luncheon at Buckingham Palace on Dec. 18. It was released on Friday to celebrate the start of 2020.

It is only the second time a portrait has been published by Buckingham Palace of the Queen, 93, her son Charles, grandson William and great-grandson George. The first was issued in 2016 when the Queen turned 90 — and amusingly showed little George standing on some books.

The latest portrait was taken by the same photographer, Ranald Mackechnie, in the Throne Room at the palace. George sports a pair of tartan pants (a rare fashion change for the future king!) in the photos, while the Queen smiles beside him in a light blue dress while carrying her signature purse.

British Royal Family
Credit: Ranald Mackechnie

The Queen entertained her extended family for a pre-Christmas party at the palace on Dec. 18. They also used that occasion to document a fun moment of the four royals mixing and preparing a Christmas pudding — with George astonishingly keeping the sticky mixture away from his bright white Amaia shirt!

Prince Charles, Queen Elizabeth, Prince George, Prince William
Prince Charles, Queen Elizabeth, Prince George and Prince William in 2016

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The Queen is currently staying at Sandringham House, in Norfolk, where she traditionally spends her Christmas and New Year period with husband Prince Philip. She was joined by most of the royal family, including George and his sister Princess Charlotte, 4, for the festivities.

A woman who met the royal siblings during their debut walk to church with their parents, Prince William and Kate Middleton, said their manners were “outstanding” and “perfect.”

The Duke and Duchess of Cambridge and their children Prince George and Princess Charlotte arriving to attend the Christmas Day morning church service at St Mary Magdalene Church in Sandringham, Norfolk. (Photo by Joe Giddens/PA Images via Getty Images)
Kate Middleton, Princess Charlotte, Prince William and Prince George at Christmas 2019
| Credit: Joe Giddens/PA Images via Getty

Raising their children is William and Kate’s most important role as they continue their ongoing training and preparations for their ultimate destiny – to be King and Queen.

“They know what’s coming [as they near the throne] and want to give their kids as normal a start as possible,” an aide told PEOPLE.