Prince Harry, William 'Uncomfortable' Around Each Other But 'Trying Their Best' To Get Along: Report

Prince Harry and Prince William have put their differences aside in honor of their grandmother Queen Elizabeth II.

The royal brothers, who reportedly have been estranged since Prince Harry stepped back from royal duties, publicly reunited and seemingly put on a united front after the Queen passed away at the age of 96 on Sept. 8.

The Duke of Sussex has found it "difficult" being in his older brother's company at times over the past week, an unnamed source close to Prince Harry told the Sunday Times of London.

But although spending time with each other has been an "uncomfortable" experience for the siblings, "everybody is trying their best," the insider claimed.

An anonymous friend of Prince Harry and Prince William also told the outlet that the brothers' recent joint appearances took "effort" and that both royals understood that it was necessary to show "solidarity."

"I don't think it goes much beyond that. There have been some awkward moments this week," the source told the Sunday Times of London. "I definitely don't get the sense of any deeper meaningful rapprochement or a sense that this is it: things will be mended."

The Prince of Wales and his wife Kate Middleton made a public appearance alongside Prince Harry and his wife Meghan Markle as a foursome for the first time in two years on Sept. 10, when they greeted mourners and viewed floral tributes and cards laid outside Windsor Castle in honor of the late monarch.

Kensington Palace confirmed that Prince William invited his younger brother and sister-in-law to join him and the Princess of Wales on the walkabout.

King Charles III's eldest son made the move because he believed that it "was an important show of unity at an incredibly difficult time for the family," an unnamed source previously told People.

Prince William and Prince Harry also sat down for dinner together, along with their wives and other royal family members, inside Buckingham Palace in London after receiving Queen Elizabeth II's coffin Tuesday evening, Page Six confirmed.

On Saturday, the royal siblings reunited once again to stand vigil – alongside their cousins – by the Queen's casket.

Prince Harry wore his military uniform to the vigil after getting special permission from King Charles III. However, the Queen's initials "ER" were reportedly removed from his uniform, which was said to have left Prince Harry "devastated."

"He is heartbroken," an unnamed friend told the Sunday Times of London. "To remove his grandmother's initials feels very intentional."

Prince Harry celebrated his 38th birthday quietly on Thursday.

While speaking to well-wishers at Sandringham that day, Prince William reportedly assured the crowd that he had not forgotten his younger brother's birthday.

The Prince of Wales told one well-wisher: "It is his birthday today - you're absolutely right, it is," The Sun reported.

Asked if he'd forgotten, the heir to the British throne reportedly laughed and insisted, "No, I've not forgotten."

The senior members of the royal family did not acknowledge Prince Harry's birthday on social media, sparking various speculations, according to royal expert Kinsey Schofield.

"Harry and Meghan are emotionally spent," the "To Di For Daily" podcast host told Fox News Digital. "The royal family typically wishes Harry a happy birthday on social media. A post had likely already been curated and approved prior to the death of the queen. Royal watchers are debating whether the lack of a post is out of respect for the circumstances or if the palace recognizes the real mix of reactions when it comes to the Sussexes presence in the U.K. right now."