• A royal author said Prince William felt "that he has to defend his family" following Harry and Meghan Markle's racism claims
  • She said it was "very unusual" for him to publicly respond to the press' questions because he normally does not 
  • Prince William was reportedly "beyond livid" over the Sussexes' interview

Prince William responding to Prince Harry and Meghan Markle's disturbing allegations of racism against the monarchy during an engagement was "very unusual," a royal author said.

Earlier this week, the Duke of Cambridge shut down the racism claims that stemmed from Prince Harry and Markle's bombshell interview with Oprah Winfrey, including that some in the royal family had been concerned over how dark Archie's skin would be. He told reporters Thursday during a visit to an East London school that they are "very much not a racist family" and that he has yet to talk to his brother but plans to do so.

Royal expert Katie Nicholl, however, said that it was out of the ordinary for the second in line to the throne to address matters concerning him or the royal family in this way.

"It was very unusual for Prince William to answer. I mean, Prince Charles was on an engagement earlier this week, and a member of the press called out ...[and] Prince Charles didn't comment -- [but] William did," Nicholl told Entertainment Tonight. "He answered not once, but twice. I think that's very telling of his mood at the moment."

Nicholl noted that Prince William is known for being "a consummate professional when it comes to being on engagements," before weighing in on his statement.

"He's done this for a very long time and I think he was probably very prepared for a question to be asked. His answer was pretty to the point, it was pretty swift, it was very much off-the-cuff” she continued. "The fact that he answered two questions was really very, very unusual. I think highly significant."

Nicholl said she was told Kate Middleton's husband was "beyond livid" over the Sussexes' interview. The "Harry & Meghan" author believes that Prince William spoke up at the time because he felt that he had to "defend his family" and that was what he did.

The royal expert went on to say that she is hoping that the two princes will be able to mend their broken brotherly bond in the future.

"I think everyone hopes that the brothers will be able to heal this rift, clearly it does run deep. I think it speaks volumes that William hasn't yet picked up the phone to call his brother. I think that he's clearly needed some cooling off time. I think the feeling though is that time is a healer. That's something that Harry himself said," she added.

Prince William was also devastated by Prince Harry and Markle's interview because his wife was dragged into the controversy, according to an earlier report. Markle told Winfrey that the reports that she made Middleton cry were not true because "the reverse happened." The pregnant duchess also said everyone knew the truth, but no one spoke up to correct it.

Prince William, Kate Middleton, Meghan Markle and Prince Harry
Prince William, Kate Middleton, Meghan Markle and Prince Harry leave after attending Christmas Day Church service at Church of St Mary Magdalene on the Sandringham estate on Dec. 25, 2018 in King's Lynn, England. Getty Images/Stephen Pond