When the royals once affectionately known as the "Fab Four" emerged from the gates of Windsor Castle, a ripple of shock spread through the gathered crowd.
Prince William and his brother Harry, joined by their wives Kate and Meghan, came together to view the flowers and cards left for their late grandmother, the Queen.
Amid rumours of a huge rift between the couples, it was the first time they had all been pictured together in two-and-a-half years.
But the photo opportunity almost didn't happen.
Royal reporters were initially told that just the newly minted Prince and Princess of Wales would be making an appearance.
Then suddenly the event was delayed by 45 minutes so that palace aides could arrange for Prince Harry and Meghan to join them.
The invitation came from Prince William, a spokesperson confirmed, with reports suggesting he texted his brother asking that they make a joint appearance after the Queen's death.
It was a poignant moment for the pair and a powerful symbol of unity.
Twenty-five years ago, William and Harry were two small boys dressed in black suits, looking stunned and lost as they viewed the flowers left for their mother who was killed in a car accident.
In the decades following Diana's death, the brothers remained extremely close.
But their relationship fractured when Harry broke away from the royal family amid accusations that his wife was subjected to racist abuse.
As the couples mingled with the crowd, dispensing hugs and accepting bouquets before climbing into the same car and driving away, it almost seemed as if reconciliation was possible.
"It is, without a doubt, a significant moment in the history of the relationship between the two brothers," royal reporter Omid Scobie tweeted.
But after a tumultuous few years, the couples are about to embark on two very different journeys.
While Kate and William are ascending to new levels of prominence and power, Harry and Meghan's position in the royal family has never been less certain.
With the accession of Charles to the throne, the King's former title as the Duke of Cornwall has automatically passed onto the next-in-line, Prince William.
But to the surprise of many, King Charles III was quick to bestow his son and heir with another title, one that was gifted to him at just nine years old and went on to hold for a record amount of time.
"Today, I am proud to create him Prince of Wales, Tywysog Cymru," King Charles III said on Friday night, just a day after his mother's death.
It has been more than 30 years since the Princess of Wales title was actively used by a senior royal family member.
Though Camilla inherited the name upon her marriage to Charles, she never used it out of respect for her predecessor, Diana.
It will now be up to Princess Catherine to confront the title's complicated legacy and the shadow cast by the beloved figure who redefined the role.
Already there have been mixed opinions on the passing down of the former prince's title, particularly in Wales.
An ITV/YouGov opinion poll of 1,020 people in June 2022 suggested that 46 per cent of people thought there should be another Prince of Wales, while 31 per cent did not.
Yet the future Queen appears to be keenly aware of the task ahead, with a source telling the BBC, Kate wants "to look to the future as she creates her own path".
The Prince and Princess of Wales have also become custodians of a sprawling and lucrative estate known as the Duchy of Cornwall, a significant step up in their responsibilities in 'the Firm'.
The prized estate, with a net worth reportedly above $1.6 billion, was established in 1337 by King Edward III for his son and heir Prince Edward, "to preserve the state and honour of the said duke according to the nobility of his kind".
The Duchy has also been used to support several other members of the royal family, including Prince William and Harry before he stepped back from his royal duties.
Its portfolio extends well beyond the geographical boundaries of Cornwall to include 52,449 hectares of land across 20 counties as well as livestock farms, granite quarries, forests and the Oval cricket ground in Kennington.
But the bulk of its income stream reportedly comes from its commercial property holdings, investing in assets such as offices and retail parks, the Financial Times reports.
The Duchy might also allow the couple, already worth millions, to level up on their real estate too.
King Charles III and Camilla's former residence of Highgrove - including the house, garden and Duchy Home Farm - are all owned by the private estate.
Though, for now, the family might be satisfied with their existing portfolio of Anmer Hall in Norfolk, their apartment at Kensington Palace and their "humble" cottage called Adelaide, near Windsor Castle.
William and Kate moved to Adelaide - considered, by royal standards, to be a modest home - in August.
Friends told the BBC it was the beginning of a new chapter to ensure as normal an upbringing as possible for their three children.
But that desire might become harder to act on now that the couple have a vast Duchy to look after.
King Charles III - who is credited with transforming the estate into a "sustainable, financially viable" venture that is of "meaningful value to the local community" - has described the task of overseeing the estate as quite time consuming.
"He's quite lucky because I found myself there at 21. I had a bit of baptism of fire really," Prince Charles said of Prince William taking over in 2019.
"He goes and visits different parts of the Duchy of Cornwall, and so he is learning, I hope, as time goes by."
King Charles III was said to have been "very hands on" as the estate's custodian, and Prince William has hinted previously he will be doing "much the same as what my father's doing" when he assumes the role.
For Harry and Meghan, the Queen's death also marks the loss of perhaps their closest ally inside the royal family.
During an interview with Oprah Winfrey last year, they shared their reasons behind the decision to step away from royal duties in 2020, including racism towards Meghan by members of Harry's family and a lack of support in accessing mental health treatment.
The couple went to great lengths to emphasise that the Queen had been nothing but supportive.
"I've spoken to my grandmother more in the last year than I have in many, many years," Prince Harry said, adding that the Queen would always be his "colonel in chief".
Breaking from the royal mantra to 'never complain, never explain', Queen Elizabeth issued a public response stating the whole family had been "saddened to learn the full extent" of Harry and Meghan's "challenging years".
"The issues raised, particularly that of race, are concerning," the statement read.
"While some recollections may vary, they are taken very seriously and will be addressed by the family privately.
"Harry, Meghan and Archie will always be much loved family members."
But the relationship between Harry and the new monarch, King Charles III, has been strained since the split.
Prince Harry told Oprah during the interview that his father had stopped taking his calls at one point and there was still a lot to work through to repair the relationship.
"Of course I will always love him but there's a lot of hurt that's happened and I will continue to make it one of my priorities to try and heal that," Harry said.
Since then, Harry has spoken publicly about the family's relocation to the US being a way to "break the cycle" of pain within his family, and rationalised that his father had "treated me the way he was treated".
But the family ties are still deep and Prince Harry joined his family in rushing to be by his ailing grandmother's side as news of her ill health was made public on Thursday night.
Her death has brought the family together to grieve, and the image of William and Harry side by side once again has been seen by royal observers as a genuine show of unity inside the fractured family unit.
But beyond that, there is still a swirl of uncertainty around what the changing of the guard might mean for Meghan and Harry.
Financially, it seems their position remains unchanged since the new income stream for William and Kate will have no direct impact on the Sussexes, who have been financially independent since stepping down from royal duties.
A senior Clarence House spokesperson told the BBC last year that Charles had allocated "a substantial sum" to support their transition that "ceased in the summer of 2020".
But this period of mourning will no doubt put a pause on the couple's operation to relaunch themselves into public life - on their own terms.
King Charles ascends the throne at a time of great turmoil.
As he tries to keep the monarchy, the Commonwealth and the United Kingdom together, it is in his interest to quell the drama within his own family.
In his first address to his subjects, the King offered something of an olive branch to his youngest son.
"I want to express my love for Harry and Meghan as they continue to build their lives overseas," he said after lavishing praise on his heir, Prince William.
But there are still tricky issues for the family to sort out.
Buckingham Palace is yet to clarify how Harry and Meghan's children, Archie and Lilibet, will be styled.
According to rules established in 1917 by King George V, children of the son of a sovereign may use a royal highness title "should they wish".
While the palace website has updated its page on the line of succession, Archie and Lilibet are still listed as "Master" and "Miss".
"While the website was updated for the Waleses, clearly updating love on a website doesn't quite work so we've not quite done that but clearly he does love them," a palace spokesman said.
"We will be working through updating the website as and when we get information."
There is also the looming release of Prince Harry's memoir, which could be on the shelves as early as Christmas.
The book, which publisher Penguin Random House may have paid up to $20 million for, is being marketed as an "intimate and heartfelt" account of the prince's life.
With lucrative Netflix and Spotify deals and a permanent California base, Harry and Meghan show no signs of wishing to return to their old lives within the House of Windsor.
Meanwhile, William and Kate are now even further ensconced within the heart of the monarchy as they prepare for the future as heirs to the throne.
The brothers' walk together outside Windsor Castle may be a new beginning. Or it may be the moment their paths diverge for good.