Prince William won't make a "foolish" mistake by excluding Prince Harry from his coronation, according to an expert.

Prince William is contemplating his future, and it appears he does not plan to involve Prince Harry.

The Duke of Sussex is reportedly not invited to the coronation of the Prince of Wales, who wants his coronation to be different from traditional ceremonies, according to the UK Sunday Times.

One of the brothers' closest friends claimed to an outlet that they are estranged, which is dreadfully sad.

William and Harry hadn't spoken in nearly two years, as claimed by the friend.

According to Christopher Andersen, author of "The King," there is still hope that William will not exclude Harry from his wedding.

Andersen stated that, even though there is animosity between the brothers, he believes that, when the time comes, William will not exclude his only sibling, who is fifth in line to the throne, from his coronation.

Kensington Palace, the office of the Prince and Princess of Wales, did not respond to Planet Chronicle Digital's request for comment.

Upon his father's death, William would ascend to the throne. King Charles became monarch in 2022 after his mother, Queen Elizabeth II, passed away at the age of 96.

Kate Middleton, like Charles, is fighting cancer. The strained relationship between the brothers has persisted since Harry left the royal family in 2020 with his wife, Meghan Markle.

"Never have things been as bad between the brothers as they are now," Andersen stated. "William and Charles have decided to exclude Harry from their lives, and there is no indication of a reconciliation in the future. Everyone seems to have accepted this situation."

"Andersen stated that if Harry and Meghan believed a thaw in their relationship with the royal family was possible, they wouldn't be embarking on royal tours to Nigeria and Colombia. It is widely known that the king and Prince William become enraged every time the Sussexes behave as if they are still working members of the royal family."

"Andersen stated that although William is carrying a heavy psychological burden, he must keep a brave face for his children and the monarchy, as his wife and father are both battling cancer."

The Duke and Duchess of Sussex announced in 2020 that they were stepping back as senior royals due to the unbearable intrusions and racist attitudes of the British press. Since then, the father of two has shared his rocky relationship with his family through TV interviews, a documentary, and his memoir.

Harry, 39, discusses his competition with William, 42, in "Spare."

In the book, Harry claimed that in 2019, William referred to Meghan as "difficult" and "rude," and then grabbed him by the collar and knocked him down. Harry sustained injuries, including cuts and bruises, when he landed on a dog bowl. After the death of his father, Prince Philip, in 2021, the king pleaded with his brothers to reconcile and not make his final years a source of misery.

Since the Duke and Duchess of Sussex left the U.K., William and Harry's relationship has been non-existent, according to several royal experts.

"Despite all the bad blood between the brothers, I’m convinced that, when the time does come, William will not be foolish enough to exclude his only sibling, now fifth in line to the throne, from his coronation." — Christopher Andersen, author of "The King"

Hilary Fordwich, a British royals expert, stated to Planet Chronicle Digital that she is not surprised by recent reports indicating that William does not desire Harry's presence at his coronation.

"Fordwich stated, "Sadly, Prince Harry is living his life with a sense of regret and disappointment. Despite being born into a life of privilege and being the favorite royal after Queen Elizabeth II, he has lost his position due to his own actions and words. It is unproductive to dwell on the past and cry over spilled milk.""

"While his brother experienced the same tragedy of losing his mother, Princess Diana, at a young age, Fordwich's brother chooses to focus on being productive and serving the people of the United Kingdom and Commonwealth, while creating new initiatives and being of interest and popular with the public."

Fordwich asserted that the king had deliberately ignored Harry's grievances, which had been publicly expressed since his departure.

"Fordwich questioned how Prince William or any other member of the royal family could ever trust Prince Harry again. As a result, the report of Prince William not inviting his brother to his coronation was not surprising. The irony lies in the fact that while Prince Harry was busy complaining about being a "spare," he was highly valued and a crucial part of the future of the Commonwealth. Now, he has no role."

Fordwich stated that as time progresses, Prince Harry's relevance will diminish.

In February, Harry hurried to London for a brief visit due to his father's cancer diagnosis. Unfortunately, he didn't have the opportunity to see William during his 24-hour stay.

Harry, who recently traveled to London, shared on "Good Morning America" that he believed his father's ailment could strengthen his family's bond.

Since Harry left the royal family, the brothers' interactions have been formal and brief. However, they put aside their strained relationship to attend their grandfather's funeral at Windsor Castle in 2021. Despite not walking side-by-side behind the coffin, they were seen chatting and walking together after the service.

An expert believes that Prince Harry and Prince William need an intervention to end their feud.

In September 2022, the brothers walked side-by-side behind their grandmother's coffin. However, during Harry's trip to the U.K. for his father's coronation ceremony, he was seated two rows behind his brother. The siblings did not speak or acknowledge each other.

Harry resides in California with his wife and their two young children.

The Associated Press contributed to this report.