It was a short blink and you'll miss it moment - the new Duchess of Edinburgh playfully shoulder-bumped King Charles on Commonwealth Day.
But despite it being over in mere seconds, it spoke volumes about the sweet bond between Sophie and her brother-in-law the new monarch.
Since marrying her husband Prince Edward, she has become a stalwart of the Royal Family - and was even dubbed a "second daughter" of the late Queen after they built a close relationship.
But despite her sad death, it seems the new monarch has just as much admiration for her and sees her as a key part of his slimmed-down monarchy...
Early days
Sophie's introduction to the Royal Family came in 1999 when she married Edward in a spectacular wedding at Windsor Castle.
Charles was at his younger brother's side as a supporter as he tied the knot with his bride.
Sophie, a former PR exec who once worked for Capital Radio, was born Sophie Rhys-Jones and like the Princess of Wales hails from a middle-class background with her parents sending her to private schools.
She and Edward were brought together by a mutual passion for the ancient sport of real tennis and romance blossomed between the pair.
They now have two children Lady Louise Windsor, 19, and 15-year-old James, Earl of Wessex.
Controversy
However, Sophie's early royal life was not without controversy and problems arose when she tried to combine her life as a royal with her professional career.
She was caught in a "fake sheikh" sting and accused of trying to use her status to promote her public relations business.
The "Sophiegate" newspaper controversy was hugely damaging, resulting in reports of indiscreet remarks about a string of public figures including Sir Tony Blair and Lord Hague.
It led to a lengthy inquiry into how working royals should be regulated and Sophie and Edward later stepped down from their individual careers to become full-time royals.
Bond with Queen
But despite early problems, Sophie forged a special bond with her mother-in-law the late Queen - which will have no doubt endeared her to her brother-in-law Charles.
Living just 10 miles away from Windsor Castle at their residence in Bagshot Park, Surrey, Sophie, Edward and their children frequently visited the Queen and would spend time together on long dog walks.
Sophie reportedly leant on Her Majesty when her own mother passed away in 2005 and they became close confidants.
The Queen personally invited her to travel to several church services and they're said to have watched old movies together.
And in 2021, following the death of Prince Philip, a royal source said Sophie had been a "tremendous source of comfort to the Queen."
When the Queen died last September, Sophie appeared devastated as she viewed the floral tributes left to the late monarch outside Balmoral.
Trusted worker
Since the late Queen died and Charles came to the throne, Sophie has remained among his trusted working royals that carry out engagements on behalf of the Firm - and has even been dubbed its "secret weapon".
And recently she's carried out trips to the United Nations in New York to talk about violence against women and girls - and even became the first royal to visit the Democratic Republic of the Congo.
Her position in the royal family has become increasingly more important since the departure of Prince Harry and Meghan Markle and in recent years she has chosen to highlight challenging issues.
In 2019 she publicly committed herself to supporting the UK’s work helping victims of rape, sexual violence and exploitation in war.
In total, she is patron of more than 70 charities and organisations, with interests including agriculture, fashion, supporting people with disabilities, and the prevention of avoidable blindness in developing countries.
A source previously told the Mirror: "Sophie’s growing popularity with the public is also evident and she will take on a larger public profile in a new-look monarchy of King Charles."
Playful moments
But it's not all work and no play for Charles and Sophie, and there have been several playful moments between the pair hinting at their fondness of each other.
Last year at Royal Ascot, they were seen sharing a joke with each other, and body language expert Judi James believes it showed their closeness.
She explained: "Charles is spatially close to Sophie, leaving a large gap between himself and Camilla. Sophie tends to get on with most of the royals and appears to be trusted at a very high level.
"She and Charles are seen roaring with laughter here and when Charles moves in to kiss her as they greet she seems to perform a rather cheeky facial expression, suggesting they are close friends.
"Sophie’s open-mouthed smile involves a rounding and a raising of the cheeks, making it look genuine and Charles’s face is wreathed in creases that suggest good humour in her company."
Meanwhile, Judi also spotted another very telling moment at Monday's Commonwealth Service.
In a blink-and-you-'ll-miss-it moment, a playful Sophie appeared to jokingly shoulder-bump Charles, who appeared eager to get on with proceedings.
She explained: "Whether it was the upgrade to Duchess of Edinburgh or maybe just a response to Charles’s slightly impatient-looking dithering as he waited to get on with the procession, but Sophie leant right in to give Charles a very playful shoulder-bump greeting, along with a very meaningful grin."
