Prince William and Kate Middleton
Royal author Valentine Low said Kate Middleton, seen here with Prince William, is "prepared to fight for what she wants and what she thinks is right". Photo: Chris Jackson/Getty Images/IBTimes Chris Jackson/Getty Images/IBTimes

Kate Middleton is described as a great asset to the royal family by royal authors who said that her role in the institution is not lost on King Charles III and Prince William.

Valentine Low, author of "Courtiers: The Hidden Power Behind the Crown," noted that the mum-of-two always shows her cheerful side when attending public engagements. She is ready to share a laugh or smile during conversations.

The biographer pointed out: "She has this public image of being nice and smiley and, dare I say, innocuous." But he told People that the Princess of Wales is "actually strong-minded, strong-willed and prepared to fight for what she wants and what she thinks is right".

Her steeliness came into play in the aftermath of Prince Harry and Meghan Markle's interview with Oprah Winfrey in March 2021. In the explosive sit-down interview, the couple spoke about the senior royals who raised concerns about their son's complexion before he was born.

The Duchess of Sussex likewise accused the firm of turning its back on her when she asked for help amid her mental health struggles, at a time when she contemplated suicide, and was told that it would not look good on the institution.

Buckingham Palace, on behalf of Queen Elizabeth II, released a 61-word statement in response to their allegations. The response pointedly noted that "some recollections may vary" regarding what was discussed in the interview.

According to Low, Kate Middleton was adamant that the line be included in the statement. She advocated for its use to toughen up what was initially a "much milder version" of the phrase.

The statement read: "The issues raised, particularly that of race, are concerning. While some recollections may vary, they are taken very seriously and will be addressed by the family privately. Harry, Meghan, and Archie will always be much-loved family members."

Low said of Kate Middleton's stance: "She thought it was very important this did not go unchallenged. She showed real strength and determination to make things clear that there was perhaps a different truth."

He added: "Kate thinks strategically. She is going to be queen one day and has the long-term interests of the monarchy and royal family at heart."

Simon Lewis, co-host of the BBC podcast "When It Hits the Fan," who also served as former Buckingham Palace communications chief, added that the Princess of Wales is "very much seen as a player at the centre of team Windsor". A royal source added that "she takes things seriously and thank goodness for that".

Meanwhile, another royal insider said that Kate Middleton is aware of the role the royal family plays in "building relationships globally on behalf of the U.K" and is always ready to help when needed.

The source cited the December 5 gathering at Buckingham Palace when she and Prince William helped King Charles III and Queen Camilla host over 500 members of the diplomatic corps.

"She hugely enjoyed that evening and looked really at home...It is clear that she and the King are quite close — in some respects closer to him than William," the insider shared adding: "It's only been recently that William has been closer (to Charles) — and Kate has acted as the honest broker in that."

As for his relationship with her husband, a former royal staffer said that she provides him with "directional setting" and that "she guides the family and guides him".

As for Prince William and Kate Middleton's role in King Charles III's reign, royal author Sally Bedell Smith said that they are "pursuing the initiatives that are important to them". She added that "they are not pushing to supplant the King and Camilla" instead "they are an incredible enhancement".