Prince George, who is about to celebrate his third birthday, has been busy this year - starting nursery, going on his first holiday to a ski resort, meeting US President Barack Obama and even carrying out his first official engagement in the UK.
Here's a look at the future king's life in pictures:
Making his debut
Prince George Alexander Louis of Cambridge - third in line to the throne, a future monarch and the Duke and Duchess of Cambridge's first child, was born on July 22 2013 and made his first public appearance at just one day old, outside the Lindo Wing of St Mary's Hospital in London, cradled in his parents' arms.
Dressed in the traditional cream frilly gown - a replica of the Victorian royal christening outfit - the three-month-old prince behaved himself, gurgled and blew bubbles ahead of the short service at the Chapel Royal of St James's Palace.
First Royal Tour
George joined William and Kate on their official tour of New Zealand and Australia when he was just nine months old. He was dubbed a royal bruiser for stealing other babies' toys during a playdate.
At the butterfly house for his first birthday
William and Kate were pictured together with George in a touching family portrait released to celebrate his first birthday in July 2014. They visited a butterflies exhibition at London's Natural History Museum, with the young prince fascinated by the delicate insects.
George's first public appearance in the UK since he was a newborn came as he was taken to the Lindo Wing by the Duke to meet new baby sister Princess Charlotte for the first time in May 2015. He waved at the crowds and was carried up the steps by William.
At the polo
The playful prince clambered up a bank, grabbed handfuls of grass and happily rolled around at the Beaufort Polo Club in Tetbury, Gloucestershire, as he joined Kate to watch William and Uncle Harry play polo.
George was shown tenderly cradling Charlotte when she was just a couple of weeks old. The photos were taken at Anmer Hall by Kate.
On the balcony
In what is a rite of passage for royal children, George made his first appearance on the Buckingham Palace balcony at the Queen's official birthday parade with the rest of the royals in June 2015.
Charlotte's big day
The Cambridges delighted the crowds at Sandringham at Charlotte's christening in July 2015 when George strolled hand in hand with William as the princess was pushed to church by Kate in a vintage 1950s Millson pram once used by the Queen for her children. George stood on tiptoes to peek into the pram to look at his nine-week-old baby sister.
With a Mario Testino image from Charlotte's christening taken to mark George's second birthday on July 22 2015, the next official image of George came in the form of a family photograph showing William and Kate crouching down with their two children. It was taken by photographer Chris Jelf in the Kensington Palace gardens and released in December to coincide with the announcement that two-year-old George would be beginning his school life by starting at a Montessori nursery.
Off to nursery
George's first day at the Westacre Montessori School was in January this year, and captured on camera by Kate. The toddler prince was shown near a large, colourful mural, wearing a winter coat with a small rucksack on his back. He had a happy first session and has settled in well.
In the snow
The Cambridges were pictured on their first family holiday with George and Charlotte in March in photos taken by the Press Association's royal photographer John Stillwell. George and Charlotte had their first real experience of snow during the break in the French Alps.
Appearing on a stamp
George also made his debut on a British postage stamp - as part of a series celebrating the Queen's 90th birthday. Grinning happily, he was perched on a stack of foam blocks to ensure he was placed at the right height for the photographer. George had his blond hair in a side parting and wore a smart white Rachel Riley shirt with blue piping, in the head shot on the first class stamp.
Meeting Obama in his pyjamas
George was pictured meeting Barack Obama just before bedtime at Kensington Palace after the US president visited the UK to congratulate the Queen on turning 90 in April. Dressed in check pyjamas and a fluffy white dressing gown embroidered with his name, two-year-old George was allowed to stay up late, and shook Obama's hand as the president crouched down to chat to him.
The Queen's 90th
To mark his "Gan Gan's" official 90th birthday in June, George joined one-year-old Charlotte for her debut on the palace balcony as the royals watched the flypast at the end of the Trooping the Colour celebrations.
George's outfit - short sleeved white shirt with peter pan collar, edged in a blue trim and blue shorts - was the same one his father William wore nearly 32 years ago to Prince Harry's christening in 1984. William was reprimanded by the Queen who told him to "Stand up" when he was crouching down to point out the incoming planes to George.
At the air tattoo
The prince donned blue ear defenders as he joined his parents on his first official engagement in the UK. He stole the show at the Royal International Air Tattoo as he was shown the inner workings of a helicopter and the cockpit of a Red Arrow Hawk as the family enjoyed a trip to RAF Fairford on July 8.
Shortly after his arrival, George broke down in tears - but was comforted, picked up and cuddled by Kate. But he performed his royal duty - waving to the crowds - even giving a thumbs up.