Prince Charles is said to be struggling with the continuing feud between his sons, Prince William and Prince Harry.

A pal tells PEOPLE in this week’s issue that Charles is “shellshocked by it all.”

“He is very hurt and upset [by the ongoing fallout].”

While their grandpa’s funeral in April reunited the family for the first time in a year, the Duke of Cambridge, 39, and Duke of Sussex, 36, allegedly ‘didn’t have time to heal’ – and are due to be together once again for the Diana statue launching on Thursday, 1 July.

“Everyone was optimistic,” according to the source. “But nothing really happened.”

“There was not really any time to build bridges,” said another intimate source.

A source informed Vanity Fair this week that the brothers are in contact and are planning a ceremony to dedicate a Kensington Palace sculpture of their late mother next week. “They know the eyes of the world will be on them—watching their every move—so what you will see is a carefully choreographed show of unity for that day, at least,” the source said.

The Diana statue was commissioned to commemorate Princess Diana’s death on the twentieth anniversary of her death and to recognize her positive influence in the UK and across the globe.

The Prince of Wales, Prince William and Harry’s father, is allegedly not intending to be present for the Duke of Sussex’s visit on Thursday.

Kate Middleton, a possible mediator, is expected to attend the event, according to the Mirror. “The Duchess has seen this project evolve from its conception and now to the finished article and undoubtedly wants to be there to support her husband,” a royal insider said. “No doubt there will be tensions between the Cambridges and Harry, but they all recognize that despite the obvious and deep rooted issues between them, they want the day to be solely about the Princess of Wales’s enduring legacy.”

The rift between the brothers started when William voiced worry about the pace at which Harry’s relationship with then-girlfriend Meghan Markle was progressing before to their May 2018 wedding, as previously reported by PEOPLE.

Royal biographer Robert Lacey, who also serves as an official consultant on Netflix’s “The Crown,” has revised his book “Battle of Brothers: William and Harry – The Inside Story of a Family in Tumult” with additional chapters and information. The British historian addressed the royal family’s continuing problems in the original book, which was released in 2020.

According to Lacey’s new chapters, things deteriorated again in October 2018 when William, 39, heard of accusations of bullying from employees.

According to Lacey, Harry, 36, was outraged by what he saw as unfounded accusations about his new wife and was “equally furious” that his brother would give the claims credibility.

Lacey said that the heated argument began over the phone and later in person when William confronted Harry about the bullying allegations.

“When Harry flared up in furious defense of his wife, the elder brother persisted,” the snippet reads.  “Harry shut off his phone angrily, so William went to speak to him personally. The prince was horrified by what he had just been told about Meghan’s alleged behavior, and he wanted to hear what Harry had to say. The showdown between the brothers was fierce and bitter.”