Prince Harry was "furious" when Prince William questioned his relationship with Meghan Markle, new book claims

[It has long been known that Prince Harry's friction with the royal family was triggered by his marriage to Meghan Markle. A new book sheds further light on what happened behind closed doors when Harry introduced Meghan to his family.

Brothers and Wives: Inside the Private Lives of William, Kate, Harry, and Meghan (opens in new tab) by Christopher Andersen was published on November 30. In it, Andersen reveals a new palace source that shares additional information about the family rift.

"Prince Harry became so furious when his brother Prince William questioned his burgeoning romance with Meghan Markle that he blurted out, 'Who do you think you are?'" according to Page Six.

"The alleged September 2017 rant happened when Harry suggested he was about to propose to his American girlfriend," the article continued, "and William asked 'why the rush?'"

According to Andersen, people close to Harry had been worried about the marriage since shortly after Harry went on a blind date with Markle in July 2016.

"One of the skeptics was his uncle, the Earl Spencer, brother of the late Princess Diana. According to Andersen, William's appointment of his uncle "made matters much worse" between the brothers. Harry was "furious that his brother was actively trying to get others to interfere in his personal affairs," Andersen said.

The book also claims that the famously reserved Harry, the eldest son of Princess Diana and Prince Charles, became increasingly concerned about reports about Meghan's father and estranged half-brother. Andersen described the protracted drama as a nightmare that "discouraged" Harry and Meghan and "terrified" William.

On one occasion, William is said to have told someone close to him: "I don't know what to believe." Andersen writes that Prince William also shared his concerns with Prince Charles, who said that Harry's relationship was "like nothing he had ever seen."

"William continued, 'I feel like I've lost my best friend,'" Page Six wrote.

In Harry and Meghan's March interview with Oprah Winfrey, Harry described his current relationship with his brother as "in space right now," but expressed hope that the rift between them will be bridged. Said the prince, "I hope that time will heal everything."

Despite the distance, royal sources said that Prince William and Kate Middleton intend to send Christmas presents to Harry and Meghan's children Archie, 2, and Lilibet, 6 months.

"Yes, of course," royal expert Katie Nicole told OK! Magazine when asked if the Cambridges will send gifts to their families across the pond." They send gifts to their entire family, so that includes all of their nieces and nephews."

Despite the reported invitation to spend the holidays with the royal family in Sandringham, Harry and Meghan will likely celebrate at their home in California.