Prince George Celebrates Milestone 10th Birthday by Starring in a Brand New Portrait

Happy birthday, Prince George!

Kate Middleton and Prince William’s eldest child turns 10 on Saturday, and they’re marking the milestone occasion by continuing an annual tradition: releasing a new photo of the birthday boy.

The photograph was taken in Windsor earlier this month by Millie Pilkington, according to Kensington Palace. Looking more grown up than ever in the new image, George is seen smiling for the camera as he sits on steps wearing a button-down shirt and long pants.

Prince George’s new pic is reminiscent of a series of snaps taken in November 2014, when the 1-year-old royal posed on another set of steps at London’s Kensington Palace for portraits released ahead of Christmas that year.

Pilkington has been behind the camera for several photos for the Prince and Princess of Wales’ family recently, including this year’s birthday portraits of Prince George’s younger siblings, Princess Charlotte, 8, and Prince Louis, 5. Pilkington also snapped Prince William with his three children for portraits released last month to celebrate Father’s Day.

The Prince and Princess of Wales have released official portraits for every one of George’s birthdays. When he turned 1, they issued a set of beautiful photos of him and his parents taken at London’s Natural History Museum at a butterfly exhibit.

Although a professional photographer sometimes captured the snap, Kate often got behind the camera herself to take the perfect birthday photo of her son.

Prince George will likely celebrate his birthday out of the public eye with his family. It’s possible the Prince and Princess of Wales, both 41, have taken their three children on a summer vacation as they have in years past on George’s big day.

With school out for summer, George stepped out at two events last week — a family outing at the Royal International Air Tattoo on Friday and the men’s final at Wimbledon over the weekend. Prince George and Princess Charlotte cheered excitedly as they watched Carlos Alvaraz defeat Novak Djokovic from their front-row seats in the Royal Box at Centre Court.

Despite Prince George’s role as future king, something he’s known for years, Prince William and Princess Kate strive to give their three kids conventional childhoods filled with playing outdoors, experimenting in the kitchen and visiting the candy store.

“It’s a massive balancing act,” a palace insider tells PEOPLE. “William and Kate are doing the right thing, protecting him so he can have as normal a childhood as possible, but he’s also dipping into duties as a future monarch.”

The insider adds, “He’s getting firsthand experience of what it’s like to be a royal and a monarch and firsthand experience of being a normal boy.”

And while Prince George can appear shy at royal engagements compared to his two siblings, a close family friend tells PEOPLE that George is a “cracking lad.”

Adds British children’s wear designer Amaia Arrieta, whose clothes the three children have worn for years: “I think George knows the drill by now. You can see he’s really grown into it and looks more relaxed than ever.”

Prince George has shown glimpses of his spirited side, especially when joining Prince William and Princess Kate at sporting events. The young royal has exuberantly rooted for his father’s favorite soccer team, Aston Villa, at games and memorably celebrated goals as England advanced to the finals of the Euro 2020 tournament. More recently, he was spotted eating pizza at a cricket match.

George is also “really sporty” himself, according to Arrieta. “It’s something that’s been encouraged from an early age,” she adds. Princess Kate previously revealed that her son is even playing rugby: “Because he is tall, he has the physique.”

The Princess of Wales’ non-royal background has a big impact on how the couple is raising Prince George, Princess Charlotte and Prince Louis.

“Those children look pretty happy with life,” a palace insider tells PEOPLE. “A lot of it is the stabilizing normality Kate brings — and that’s how she grew up. William absolutely loves it.”

Prince William and Princess Kate “consciously set out to achieve a sense of normality,” says a close source, and the couple was given permission by Queen Elizabeth and then-Prince Charles to focus on family above royal duties while they raised their young children — a distinct change from how their own royal childhoods.

“Royal families over the generations haven’t had the chance to get those foundations right, but they have,” says a friend.