George giggles with Charlotte and Louis in behind-the-scenes 12th birthday video

Behind-the-scenes footage of Prince George having fun with his siblings Princess Charlotte and Prince Louis has been released to celebrate his 12th birthday.

George is shown laughing as he and Charlotte both lift a giggling Louis up in their arms during an outdoor photoshoot, with George holding his younger brother around his chest and Charlotte holding his legs.

The upbeat video montage, filmed by Kensington Palace’s in-house social media team, shows the trio smiling as they stride along holding hands in the sunshine, with Louis in the middle of his brother and sister.

The royal siblings also pose for a family portrait with Charlotte and Louis sitting on a rustic wooden gate as George leans next to them.

The Prince and Princess of Wales released a new solo colour photograph of their eldest child George, taken when the video was shot, to mark him turning 12 on Tuesday.

The future king – one year away from being a teenager – is pictured smiling and relaxed as he leans on the gate in the Norfolk countryside.

George is wearing a white checked shirt with rolled up sleeves and a dark green fleece gilet, and a blue and white friendship bracelet can be seen on his left wrist as he rests his folded arms on the gate.

A screenshot from a video of George, Louis and Charlotte holding hands during the photoshoot (Kensington Palace/PA)

The image, posted on Kensington Palace’s social media, was taken by photographer Josh Shinner earlier this year.

It was accompanied by the message: “Happy 12th Birthday to Prince George!” followed by a cake emoji.

The royal family also sent its congratulation to George, wishing him a “very happy birthday”.

George, whose birthday falls during his summer break from school, has one year left at his prep school Lambrook before he moves on to his senior school – with either Eton or Marlborough College thought to be the frontrunners.

The prince joined his parents and sister Princess Charlotte at the Wimbledon men’s final earlier this month, where he used a fan to keep cool in the royal box in the blazing afternoon sun.

In June, George was seen nudging his boisterous younger brother Louis on the Buckingham Palace balcony to wave more calmly at the crowd following the Trooping the Colour ceremony.

The Prince of Wales and Prince George at Wimbledon (Andrew Matthews/PA)PA Wire/PA Images - Andrew Matthews

Prince George Alexander Louis was born in the private Lindo Wing of St Mary’s Hospital, Paddington, London, at 4.24pm on July 22 2013, weighing 8lb 6oz.

He made his debut in front of the world’s media on the hospital steps one day later, wrapped in a white Merino wool shawl, cradled in his mother’s arms.