The reconciliation between King Charles and Prince Harry is not impossible, but will take time, according to an author.

Peace talks between King Charles and Prince Harry won't be simple, despite the king's desire to reconcile with his estranged son.

Robert Hardman, author of "The Making of a King: King Charles III and the Modern Monarchy," made the claim.

The Duke of Sussex will only be able to speak with the king again once he stops publicly airing his grievances, according to Hardman.

"Could Harry return to royal life? That's a common question. However, the royals never say never. A good starting point is for Harry to visit the U.K. and see his father with his kids, and Meghan Markle if she desires."

"It's going to be a slow burn, yes, but no, the door is not slammed shut." — Robert Hardman, author of "The Making of a King: King Charles III and the Modern Monarchy"

"Hardman stated that he believes the Duchess of Sussex does not enjoy visiting Britain, but if she occasionally comes to see her grandfather, it can become normalized and they can start building from there."

"Although it will be a slow burn, the door is not slammed shut," he said.

If Harry ever wants to return to the royal fold in any capacity, Hardman believes he should make peace with his father. Prince William, the heir to the British throne, is described as "very dutiful" by Hardman, who says he will prioritize the crown over his relationship with his younger sibling, which is said to be non-existent today.

"Hardman stated that William is less radical than his father, and they have different opinions on certain things. However, they work together as a team. The conversation took place after Queen Elizabeth II's death in 2022, during a gathering at Balmoral Castle. Charles, Camilla, and William were the only ones who were not saddened by the dinner, as they had gone to Charles' place to plan their next steps. They emphasized the importance of being a team."

"Despite Queen Elizabeth II's decline in power and the king taking on more of her duties, William felt the need to take on more responsibilities. This is why William and Charles have a good working relationship. Historically, there have been great tensions between the monarch and the heir to the throne. However, this hasn't been the case in modern times."

Since turning 40, Harry has been experiencing "the birthday blues," according to a source who spoke to royal expert Neil Sean. On Sept. 30, the father of two attended the annual WellChild Awards in London, a charity he has continued to support since stepping back as a senior royal.

"Harry expressed his desire to obtain an opinion on his position in the U.K. market and admitted to having birthday blues about turning 40, but also stated his excitement for the upcoming decade. The source explained that Harry's reasoning was that "nobody knows where life is taking them, right?""

The insider revealed to Sean that the prince confessed that he loves the WellChild Awards because it makes him reflect on his life and realize that his problems are minor compared to the struggles faced by these courageous children. The source stated that Harry yearns for the U.K. every day.

If Harry had his way, he would consider living in London full-time again, but "once you have children, your life is no longer your own."

The Duke and Duchess of Sussex have two young children, Prince Archie, 5, and Princess Lilibet, 3, who are being raised in California.

"The source informed Sean that during the conversation, the individual asked if he had read his autobiography and if it had altered his opinion of him. The person appeared enthusiastic about this specific line of questioning, and it was discovered that he had mentioned it to others as well. Upon departure, the individual was cheerful and optimistic."

"The source stated that he believed that despite his portrayal, his life was not fully satisfied. However, it was evident that he had made every child in the hotel room feel special, and for that, everyone should be grateful."

Sean believes that Harry desires to return to his homeland, but the individuals he must persuade are his family, specifically the royal family.

Charles had been advised by Hardman to avoid responding to Harry's communications in order to reduce his stress, as previously stated by Hardman to Planet Chronicle Digital.

"Hardman explained that while people often ask why the king doesn't see Harry when he's in town and why they can't fix their relationship, the current focus is on managing the king's stress levels. It's important not to add any extra burdens to his plate. Let's prioritize getting through this difficult time. There is a sense that now is not the right time to address these issues."

"Harry has a lot to unpack in his TV series, book, and interviews, according to Hardman. He wants to sort out things before going through the process. However, there's a sense that it's not the right time yet. But the king would like to normalize things, Hardman shared."

A Buckingham Palace representative did not immediately respond to Planet Chronicle Digital's inquiry for comment.

Since 2020, Harry has had a strained relationship with his family due to his and his wife's decision to step back as senior royals, citing unbearable intrusions and racist attitudes from the British press.

Since his rocky relationship with his family became public, the father of two has shared his story in TV interviews, a documentary, and his memoir, "Spare."

In March 2021, Harry revealed in an interview with Oprah that the king had stopped answering his calls prior to his departure with his wife.

The prince's friend told People magazine that safety and a lack of support from the palace were always top priorities for him.

In July, sources revealed that Harry is planning to challenge a court decision that maintained his security denial. The Duke of Sussex aims to restore his security to facilitate more flexible trips to the U.K. for him, his spouse, and their two kids.

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The sources claimed that the issue plays a significant role in Harry's ongoing estrangement from his father.

Harry lost his personal protective security, which was funded by taxpayers, after he relinquished his royal family status.

"The only option was to leave for their sanity," the pal told the outlet. "They thought if they got out of this bubble, there would be less focus on them."

Some close to the palace believe that Harry's memoir and interviews have damaged the family's trust in him, while those close to the prince argue that if he had proper security, he wouldn't need to speak publicly to pay for it.

If the security issue is resolved, "it’s swords down," claimed the friend.

"Being able to rekindle his bond with his father would bring [Harry] the most happiness," the pal said to the outlet. "Despite the fact that you can't change bloodlines, Harry isn't asking for material possessions. He's asking because of the reality of the situation. He's at risk."

The Associated Press contributed to this report.