His pensive little face as he approached the gates of his new school last September, gripping his father's hand, will have tugged at the heart-strings of every parent.
Since then, it's a look that has become all too familiar. Rarely is there a royal gathering without the sight of Prince George looking nervously towards the cameras, his anxiety all too evident.
It's in sharp contrast to the bouncy confidence and mischievous twinkle of little sister Charlotte, who never disappoints snappers with a wave (or even a cheeky comment, as we heard at Prince Louis's christening last week).
It is an image of George, however, that friends of the Duke and Duchess of Cambridge insist belies the happy, confident child their firstborn is developing into. Tomorrow, George turns five and will be celebrating his milestone birthday on the Caribbean island of Mustique, the Daily Mail reports.
The family left London on Monday and have been joined by grandparents Carole and Michael Middleton, and aunt Pippa and her husband James Matthews, so it will be quite a party.
One day, the third in line to the throne — who wants to be a pilot, just like his adored 'Papa' who flew with the East Anglian Air Ambulance — will learn his life choices are somewhat restricted.
For now, his parents are focused on providing him with the close-knit, carefree family life that mum Kate took for granted as she grew up — and that William's own late mother, Diana, Princess of Wales, fought to try to give her two boys.
The past year has been a formative one for George; the family moved back to London from their cloistered life at Anmer Hall, on the Queen's Sandringham Estate in Norfolk, and he started school.
His nerves on his first day at Thomas's Battersea, in West London, were apparent, despite his parents arranging for a discreet, five-strong group of media to capture the moment, as opposed to the hundred-plus assembled to document William's arrival at prep school at the same age.
The duke admits his own experiences as a young boy — the mass photocalls and what he views as an overwhelming public interest in himself and brother, Harry — had been hard to deal with.
He has made clear that he will be much more cautious with his own children, striking a careful balance between allowing people to share in their growing up, without making the youngsters feel they are constantly in the public eye.
Some have questioned whether William and Kate's understandable protectiveness of their son, plus their instinctive wariness of the media, may have inadvertently rubbed off on George. But friends insist he is no different from other young children. "Just because he reacts more cautiously than Charlotte when there is a camera around isn't an indication of what he is like behind closed doors," says one. "Your first day at school is a big enough deal without all these strange people watching you. He is a very happy little boy."
William and Kate hope their choice of school, albeit one in the heart of an affluent area of the capital that has been dubbed Nappy Valley, will offer their son the chance to develop in a more rounded environment than other young royals.
"They thought long and hard about where George should be educated and really liked Thomas's, which has a lovely nurturing atmosphere," a source said.
"The school focuses as much on helping develop the character of pupils, as what they learn. William and Kate are keen to allow George to spread his wings and make friends at this stage.
"They know there will come a time when they will have to sit down and talk to him about the implications of his royal status and why so many people are interested in him. He is becoming more aware of the cameras. But they are determined to do that at George's own pace and feel that can all wait a bit."
The couple have made a point of doing the school run themselves as much as possible. Indeed, Kate was seen dropping off her son the morning after she gave birth to her third child, Prince Louis.
And when the parents of children in the reception class held a 'get to know you' coffee morning, William turned up unannounced, dressed down in chinos, jumper and wearing his glasses. One parent tells me: "No one really gives Kate a second glance when she does the school drop-off. We have a Victoria's Secret model doing the school run, too, and the dads are far more interested in her!"
Another source adds: "George loves it. He has really thrived there. And I know they [William and Kate] are immensely grateful to the media for giving him space. It's a very happy environment for him."
In truth, those undeniably stressful photocalls apart, George is a determined little boy, and while he is often bossed around by three-year-old Charlotte, his parents say he has a strong streak of mischief.
He loves the Gruffalo and Fireman Sam, planes, trains and cars. And right now he is fascinated, just as many of his school friends are, by volcanoes and lava.
At a recent polo match, he could be seen showing friends a picture he had drawn of an eruption. And while much comment has been made of the 'Little Lord Fauntleroy-esque' way Kate dresses her son in public, in private he is like any other youngster, in Crocs and grubby T-shirts, with scratches on his knees.
With three youngsters now in residence, life at Apartment 1A Kensington Palace is as chaotic as you might expect, with children running around the kitchen and Capital Radio playing loudly each morning as everyone gets ready for the school run.
Socially, the duke and duchess tend to mix with other young families, such as the Jardine-Patersons — Emilia is Kate's friend from Marlborough College and David was at Eton with William — and the van Cutsem clan (brothers Nicholas, William, Edward and Hugh, are among William and Harry's oldest childhood friends).
But there are also weekends in the country at Anmer Hall, visits to farm parks, country shows and to the Hurlingham Club in London, where George was seen happily tucking into a plate of pasta while his parents played tennis.
Another increasing feature of George's life is, of course, his royal grandfather. After what was undeniably a slightly difficult start, Charles — said to have privately railed about the amount of time he got to spend with his grandchildren compared with Kate's family — has become devoted to them.
Indeed, a charming never-before-seen private photograph which sits on Charles's desk — showing him cradling baby George with William looking on — will feature in an exhibition which opens today at Buckingham Palace to mark Charles's 70th birthday in November.
Charles's ever-increasing workload — which now includes a number of duties that traditionally fell to the Queen, particularly foreign travel — means the time he has available is limited. But Prince Louis's christening last week saw Charles host his growing family at Clarence House for what was described as a 'really fun family afternoon'.
"It is clear he is immensely proud of his sons and adores his grandchildren," one source told me. "I'd say things are better than they have been for a long time." Another said: "Charles understands that Kate gravitates to her mother and family and is actually very grateful for everything the Middletons do."
Carole, 63, and her husband Michael, 69, play a hugely significant role in their grandchildren's lives — as their current Caribbean holiday together shows. She has taken George and Charlotte to work at the family's Party Pieces HQ, a short drive from the Middletons' Berkshire mansion, where they play at being shopkeepers.
One visitor spotted George sitting in the 'front of house', exclaiming excitedly 'Oh my gosh!' as his indulgent granny gave him a bag of sweets for being a good boy.
Kate understands only too well that it is a grandparent's prerogative to spoil their grandchildren — and still laughs about how she once called home from a foreign tour to speak to her mother, who was looking after George, only for him to tell her earnestly that his granny had given him 'chips, again' for dinner.
With a loving, extended family around him, determined to protect him from the pressures of royal life for as long as they possibly can, it's no wonder that George is growing into such a settled little boy.
And who knows, one day he still may be able to become a pilot — just like Papa.