When Meghan, the Duchess of Sussex, made a surprise appearance on CNN's "Heroes" special this week, she stood out in a conservatively chic blouse that did not distract from her message on the power of the human spirt amid the coronavirus pandemic.

When the new season of "The Crown" debuted on Netflix last month, viewers got a dazzling look back at the fashion evolution of the late Princess Diana and the power of her clothes.

And when Duchess Kate stepped out for a train tour with Prince William this month, she used different outfits to draw attention to the different stops she and William made to thank essential workers and volunteers.

"It's important to remember that a big part of these women's job is just to appear in public and to understand the amount of fanfare and attention those appearances get," said Elizabeth Holmes, the author of " HRH: So Many Thoughts on Royal Style," a New York Times bestselling book on the fashion of Meghan, Kate, Diana and Queen Elizabeth. "These women don't give big, revealing interviews by and large. They don't give big speeches. What they do is they step out in public, and what we see first is what they're wearing."

Holmes, a former Wall Street Journal fashion reporter, uses her book and her "So Many Thoughts" brand on Instagram, to, as she says, "connect the dots" for people on the messages royal women send with their clothes, and the power in that.

"We can have a much bigger discussion about the burden of presentation that's placed on women versus men and I think that's an important one to have, but the fact of the matter is the attention is there," she said. "The royal family knows that and I think it's very savvy that they harness it and they use it to further their work."

PHOTO: Members of the royal family, from left, Queen Elizabeth II, Meghan, Duchess of Sussex, Catherine, Duchess of Cambridge, and Princess Diana.
Getty Images, FILE
Members of the royal family, from left, Queen Elizabeth II, Meghan, Duchess of Sussex, Catherine, Duchess of Cambridge, and Princess Diana.

With so much focus on the fashion of the women of Britain's royal family, Holmes broke down five common myths around the looks of Queen Elizabeth, Diana, Kate and Meghan.

PHOTO: The cover of the book by Elizabeth Holmes, "HRH: So Many Thoughts on Royal Style," published in 2020.
Celadon Books
The cover of the book by Elizabeth Holmes, "HRH: So Many Thoughts on Royal Style," published in 2020.

Myth #1: Royal fashion is frivolous.

Holmes said about the interest in royal fashion, "I care because [the royals] care and they care because they know the world is watching."

Though royal fashion has been a source of fascination for centuries, it was Princess Diana who elevated the use of fashion as a way to draw attention to important issues, according to Holmes.

"Diana made royal fashion exciting," said Holmes. "Her clothes were a reason to pay attention to the royal family and the work that they're doing and Diana knew that. She delighted in it."

"Fashion is such a part of her legacy and then when Kate [the wife of Diana's oldest son, Prince William] came onto the scene a decade later, we were all primed to care about royal fashion, because of what Diana had done with it," she said.

Myth #2: That royal women have written fashion rules they must follow.

There is no rule book or fashion guide book that is handed to royal women on things like what nail color polish to wear or the length of a dress, according to Holmes.

Women like Meghan, Kate and Diana who marry into the royal family must figure out in their own way how to dress like royalty, with a global spotlight on them.

"The guardrails with which these women get dressed is one of the most interesting things to me about royal fashion," said Holmes. "They have their choice of designers, but they also have the expectations of the British public and the globe, the rest of us following along, that they look and appear a certain way."

Royal women must then figure out how to dress for their roles, without losing their own style.

Duchess Meghan, for instance, made her first public appearance as Prince Harry's girlfriend wearing distressed denim jeans and stood alongside Harry in her first Trooping the Colour appearance in an off-the-shoulder Carolina Herrera creation.

Neither broke any royal fashion "rules," but both stood out as departures from traditional royal looks, according to Holmes.

"If you had been watching royal fashion since Kate entered the family, you had in your head the Kate look. It's classic. It's feminine. It's pretty uncomplicated, especially in those early years," said Holmes. "When Meghan came in with a much more modern and in so many ways very chic look, then she brought with her a whole new audience to the royal family and to the royal fashion discussion."

Myth #3: That royal fashion can only be used for good.

Duchess Meghan, who, with Harry, stepped down as a senior member of the royal family earlier this year, has drawn attention to her work through her clothes, but also faced criticism for her choices.

"Certain things about what she wore, because they were not expected perhaps, were used against her and they were sort of a source of criticism when they were beautiful, totally appropriate, wonderful clothes," said Holmes. "To get dressed every day and to have your clothes used against you I think would be really difficult."

"Meghan's choices and her sort of boldness, it reminds me very much of Diana," she said.

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Princess Diana also faced criticism for her fashion, but reportedly from within the royal family, specifically her then-husband Prince Charles, according to Holmes.

"He often sought to use her interest in fashion as sort of evidence that she was frivolous or shallow," said Holmes. "And that to me is so sad because fashion is so powerful and Diana used it so well, and to use it against her I think is just really unfortunate."

Myth #4: That each women's fashion is not influenced by others.

When Duchesses Kate and Meghan appear with Queen Elizabeth, they are often told ahead of time what color she will be wearing and coordinate on their own from there so as not to draw attention from the queen, according to Holmes.

While Kate, who will become queen when William ascends to the throne, has become more daring in her style choices over the years, she appears to have drawn influence from Queen Elizabeth, whose public uniform is described by Holmes as "walking the line of being stylish but sensible, fancy but frugal."

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"I do think that we'll continue to see the kind of calming consistency from Kate that we've seen from the queen," said Holmes. "I don't know that anybody will ever dress like the queen, but I do expect Kate to devise her own sort of uniform, and there's real power in that."

Holmes said she sees Princess Diana's fashion influence directly on Meghan, who wed Prince Harry more than two decades after Diana was killed in a car crash in Paris.

Meghan, a former actress, is similar to Diana in making bold fashion choices and understanding the emotion of fashion, according to Holmes.

"Diana also understood the emotion around fashion, how it made her feel and how it would wow a crowd," she said. "When we see something that we don't expect, it can be very, very exciting, and that excitement holds a lot of power because it means we're paying attention to the royal family and hopefully the work that they're doing."

Myth #5: The power of royal fashion comes only with sequins and tiaras.

For every royal fashion statement made with a ball gown and a tiara, royals also often choose clothes that are more subdued or re-worn, in order to put the attention on the issue at hand, according to Holmes.

After Princess Diana's divorce from Prince Charles was finalized, she sold many of her high-profile clothes at auction and chose more subdued looks for her charity work, like the khakis and button-down shirt she wore to draw attention to landmines, according to Holmes.

Similarly, Meghan, in her first months as a nonworking member of the royal family, chose very simple clothes as she delivered speeches via Zoom and joined remote calls during the coronavirus pandemic.

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"Therein lies the power," said Holmes. "It's not just about when they razzle and dazzle in glamorous gowns and tiaras, but it's also when they choose not to participate in the fashion discussion, when they put the emphasis completely on what they're doing or what they're saying and how they know that the attention is there and they are directing it."