The Royal Family’s official social media accounts, along with William and Kate’s Instagram and X accounts, posted birthday wishes for the Duke of Sussex

Prince Harry has received some unexpected royal birthday wishes.

The Duke of Sussex turned 40 on Sunday, Sept. 15, and his milestone birthday was celebrated by both his father, King Charles, 75, and his brother Prince William, 42, in posts on social media, marking the first time the royal family has publicly acknowledged Harry’s birthday since 2021.

On the official Royal Family social media accounts, which are run by King Charles’ office at Buckingham Palace, a post celebrated Harry’s milestone birthday with a simple message.

”  Wishing The Duke of Sussex a very happy 40th birthday today!,” the caption of the post read, alongside a photograph of the Duke smiling.

Meanwhile, the Prince and Princess of Wales shared the Royal Family’s post on their own Instagram Stories account and on X (formerly Twitter), adding their own celebratory message.

“Wishing a Happy 40th Birthday to the Duke of Sussex,” the caption above the photo read.

King Charles (then Prince Charles), Prince William and Prince Harry attend the commemorations for the 100th anniversary of the battle of Vimy Ridge on April 9, 2017 in Lille, France.Pool/Samir Hussein/WireImage 

Prince Harry Says He’s ‘Excited’ to Turn 40 in Birthday Message: ‘A Fresh Perspective on Life’

PEOPLE understands Harry will mark his 40th birthday on Sunday, Sept. 15, with a private celebration in Montecito, surrounded by family and friends. Harry is then expected to continue the festivities abroad with close friends.

The celebratory posts come as a surprise, as public birthday wishes are usually reserved for working royals—though occasionally made for milestone birthdays. Given the ongoing rift between Harry and his brother, as well as his strained relationship with their father, many see these first birthday messages in years as a potential olive branch from King Charles and Prince William.

In July, sources told PEOPLE that Harry’s calls and letters to King Charles, go unanswered, and his attempts to connect with Prince William — through texts, calls, and messages — were similarly ignored.

However, while the royal insider noted that the rift with Prince William was “very bad,” they added that it was not “irreparable.”

Prince William, King Charles (then Prince Charles) and Prince Harry in London, England in 2014. 
Prince Harry and Prince William’s Rift Is ‘Very Bad’ but Not ‘Irreparable,’ Royal Insider Says (Exclusive)

The brothers last presented a united front with their wives, Kate Middleton and Meghan Markle,  after Queen Elizabeth’s death in September 2022, when they met mourners outside Windsor Castle

At the coronation of King Charles in May 2023, Harry stayed on the sidelines and sat two rows behind William and his family. At the time, Meghan remained in the U.S. for their eldest child Prince Archie’s birthday.

When Prince Harry returned to the U.K. in May 2024 for the 10th anniversary of the Invictus Games, he did not meet with either the King or Prince William. At the time, the Duke of Sussex’s spokesperson attributed the lack of interaction between Harry and the King to the sovereign’s “full schedule.” However, sources close to Harry suggest it was because he wanted to discuss his ongoing battle for security, which he has been fighting for in court for more than four years and believes his father has the power to reinstate. (Buckingham Palace will not comment on security provisions, but a palace source previously told PEOPLE the notion that Harry’s security is in Charles’s hands is “wholly incorrect.”)

Prince Harry, Duke of Sussex and Meghan, Duchess of Sussex at San Basilio de Palenque during The Duke and Duchess of Sussex Colombia Visit on August 17, 2024 in Cartagena, Colombia. 

The family rift that first became public in 2020 when Harry and his wife, Meghan Markle, stepped back from their royal roles has been marked by blistering attacks and unresolved tensions. Yet for Harry, the most significant unresolved issue remains security.

Despite a positive meeting between the father and son in February following the King’s cancer diagnosis, communication between the two has since broken down. Those close to Prince Harry say the monarch no longer takes his son’s calls or replies to his letters.

“He gets ‘unavailable right now,’ ” a friend of Harry’s told PEOPLE. “His calls go unanswered. He has tried to reach out about the King’s health, but those calls go unanswered too.”

Amid the estrangement, Harry remains concerned for the safety of his wife and children.

A source close to the situation said, “Harry is determined to protect his own family at all costs.”