Princess Kate found putting on a show of unity with Meghan Markle and Prince Harry “the hardest thing she’d ever had to do,” according to a new biography.

Prince William invited the Duke and Duchess of Sussex to join him and Kate to inspect floral tributes to Queen Elizabeth II in the aftermath of the monarch’s death in September 2022.

The four royals had not been photographed side-by-side in public since Harry and Meghan’s final day as working royals, when they attended the Commonwealth Day Service at Westminster Abbey in March 2020.

Royal author Robert Jobson described Kate’s emotional reaction in his new book Catherine, the Princess of Wales, published by Pegasus in America on August 6.

“Amid all the grief at the Queen’s death, William, now Prince of Wales and heir to the throne, took decisive action,” he wrote. “Picking up the phone to Harry, he suggested that they and their wives put on a show of unity for the sake of their late grandmother by viewing the floral tributes at Windsor together. Harry accepted.

“The resulting images suggested they’d all slipped back into their Fab Four routine, but Catherine later admitted to a member of the Royal Family that such was the extent of ill-feeling between the couples, the walkabout had been the hardest thing she’d ever had to do.”

It was the first time Kate had been photographed in public alongside Meghan since the Oprah Winfrey interview in March 2021, in which the duchess said she had been wrongly accused of making Kate cry when in fact, she argued, the reverse had happened.

The princess had been filmed chatting politely to Harry though, after Prince Philip’s funeral in April 2021.

Jobson wrote: “At his funeral, Catherine—exuding poise, calm and regal impregnability—took her place as one of the most senior Royal Family members, supporting the frail and grieving Queen and comforting Prince Charles.

“She also deployed her diplomatic skills to try to deal with the bad blood between her husband and his brother as they both mourned their grandfather in silence.

“Harry had walked quickly towards Catherine as he left the chapel behind her husband and other family members. Subtly, she increased her pace so they could catch up with William, a few steps ahead.

“She then fell back, to allow the brothers to walk next to each other and at least exchange a few words. It gave the public the impression that they were putting on a united front for their late grandfather, a welcome mini-truce in their feud.”

Kate had been in the same room as Harry and Meghan during a service of thanksgiving for Queen Elizabeth II’s reign at St. Paul’s Cathedral in London, during the Platinum Jubilee in June, 2022.

However, they sat on opposite sides and were not seen engaging with each other.

Meghan was asked by Oprah during her 2021 tell-all about a story suggesting the duchess had made Kate cry during an argument about bridesmaids dresses.

“The narrative with Kate which didn’t happen was really, really difficult and something that…I think that’s when everything changed, really,” Meghan said. “The reverse happened. And I don’t say that to be disparaging to anyone, because it was a really hard week of the wedding.

“And she was upset about something, but she owned it, and she apologized. And she brought me flowers and a note, apologizing. And she did what I would do if I knew that I hurt someone, right, to just take accountability for it.”

In Harry’s January 2023 book Spare, he quoted Kate saying: “Charlotte’s dress is too big, too long, too baggy. She cried when she tried it on at home.”

Meghan, he suggested, replied: “Right, and I told you the tailor has been standing by since eight a.m. Here. At KP. Can you take Charlotte to have it altered, as the other moms are doing?”

Kate, according to Harry, replied: “No, all the dresses need to be remade.”

And Meghan at one stage offended Kate by suggesting she had baby brain, Harry wrote.