Who Will Play Princess Margaret in 'The Crown' Season 3? Helena Bonham Carter Possibly Confirmed by Vanessa Kirby

Will the real Princess Margaret please stand up?

The cast for Season 3 of Netflix’s acclaimed royal drama The Crown is taking shape with rumors circulating earlier in January that Helena Bonham Carter will take on the role of Queen Elizabeth’s wayward sister.

Now, original Margaret actor Vanessa Kirby has all but confirmed her royal successor by sharing an Instagram photo of her and Bonham Carter, 51, posing together. She captioned it: “Honoured.”

As has been widely reported, Netflix will recast the key roles in The Crown for its third and fourth seasons with older actors to portray the royal family as they enter their middle years.

Golden Globe winner Claire Foy, Matt Smith and Kirby, who originally played the roles of Queen Elizabeth, Prince Philip and Princess Margaret, all signed on for just two seasons.

Show creator Peter Morgan previously explained he would recast roles every two seasons because “you can’t ask someone to act middle-aged,” he told Variety. “Someone has to bring their own fatigue to it. The feelings we all have as 50-year-olds are different than the feelings we all have as 30-year-olds. That informs everything we do.”

Bonham Carter previously played Elizabeth Bowes-Lyon, Elizabeth and Margaret's mother and the wife of King George VI, in Oscar-winning drama The King's Speech.

As well as casting Bonham Carter, show creator Peter Morgan has also lined up British actor Olivia Colman, celebrated for her roles in dramas Broadchurch and The Night Manager, to play Elizabeth in the new season.

Colman told the BBC in October she is “so thrilled” to take over the role.

Vanessa Kirby in 'The Crown' Season 2 Vanessa Kirby in 'The Crown' Season 2 Alex Bailey/Netflix

"I think Claire Foy is an absolute genius—she's an incredibly hard act to follow,” said Colman. “I'm basically going to re-watch every episode and copy her."

Foy also praised Colman: "I just love her, I admire her so much and the idea that we sort of will be doing the same job but not actually working together is just enough—I'm honoured by that.”

No word yet who will replace former Doctor Who star Smith as Elizabeth’s husband Philip (some suggestions from the Newsweek team can be found here).

In December, Smith told Newsweek he did not wish to speculate who might take over his role, nor did he have any advice for his sucessor.

“I wouldn’t give them any advice just like I didn’t give Peter Capaldi advice [when he took over as Doctor Who]. They’ll find someone brilliant who’ll approach it with their own thought processes and personality,” said Smith.