The British royal family is believed to be anticipating what comes next from Prince Harry and Meghan Markle following the release of their Netflix series. But they are more concerned about what the Duke of Sussex has to say about his family in his upcoming memoir, according to a royal expert.

Royal biographer Katie Nicholl thinks that the royals are already preparing for whatever explosive revelations the 38-year-old has written in his book titled "Spare." She told OK! that the "Harry & Meghan" series has only left the royals feeling "apprehensive."

"I don't think the royal family are terrified by anything, least of all of what is going to come next in Harry's autobiography. But concerned, apprehensive? Yes. Ready to respond? Quite possibly. Wearied by all of this? Absolutely."

The author of "The New Royals" even thinks that the family will respond this time following their silence to the couple's claims in "Harry & Meghan." She thinks it is about time that they put an end to the incessant attacks against The Firm.

Nicholl explained, "Whilst I think in this instance the palace's lack of response is the right thing, there needs to be a shot across the bow from the palace to Harry and Meghan [Markle] that this is not going to be tolerated and this has to stop."

She added, "We know there is going to be an autobiography and I wonder if we will hear from the palace after the publication of the autobiography. I wouldn't rule it out."

In the six-part Netflix docuseries, the Duke and Duchess of Sussex shared a behind-the-scenes glimpse at their former royal life including the paparazzi stalking and the negative toll the British press had on the former "Suits" star.

Meghan Markle revealed that it was Queen Elizabeth II and King Charles III who advised her to write to her estranged father ahead of the royal wedding in 2018. Prince Harry also clarified that it was his decision to leave the U.K. and move to California and not his wife's. He also recalled the Sandringham summit when Prince William yelled at him for his decision to abandon his duties. All the while, the royal family has remained silent on all their claims.

Harry & Meghan on Netflix
"Harry & Meghan" six-part docuseries on Netflix Harry & Meghan/Netflix