King Charles has named four new additions to the Order of the Garter, but he’s changing things up a bit this year.

Initially, Charles planned to invest three new members, but he’s added a fourth, Birgitte, the Duchess of Gloucester, the wife of Prince Richard, the Duke of Gloucester.

Marlene Koenig, royal historian and author of Royal Musings, told Daily Express US: “She is the first spouse of a royal prince in modern times to be given the Garter.”

She added: “I think it’s way cool that Charles has made this change, giving this to someone who has served the crown, and she and her husband were never meant to have a full-time royal career.”

Ms Koenig explains Richard worked as an architect, but six weeks after his wedding, his brother was killed in a plane crash in 1972 and “everything changed.”

He became heir to the dukedom and Queen Elizabeth II asked for Richard and his wife to become full-time royals, which they agreed to, and “they have served the crown admirably.”

“This is another new change the king has implemented, and I think we’ll see more of that in another few years,” predicting Sophie, Duchess of Edinburgh, may become a Lady of the Garter.

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Princess Elizabeth was the first female heir to receive a Garter. In 1987, as Queen, she created a statute that reintroduced women to the Garter, being named full Companions of the Order.

“In 1990, Queen Elizabeth II named Lavinia Fitzalan-Howard, Duchess of Norfolk, to the Garter, and four years later, she changed how things were done, she named her daughter, Princess Anne, to the Garter,” said Ms Koenig.

“Anne said she didn’t want to be a Lady of the Garter, she wanted to be a Knight of the Garter, so she’s actually a Knight.”