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Prince George's birth, 2013 -

Prince George made his first appearance in public outside St Mary's Hospital in London just hours after his birth.

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Prince George's birth, 2013 - This was also the moment when the world saw Prince William make his debut as a father.

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First family portrait, 2013 - A few months later, the first family photo of William and Kate with their new baby son was released.

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George's christening, 2013 - A proud William holds Prince George on the day of his christening in October 2013.

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George's christening, 2013 - William looks down at his baby son as Kate chats to guests.

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Australia and New Zealand, 2014 - Six months later, in April 2014, Prince George embarked on his first royal tour abroad to Australia and New Zealand.

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Australia and New Zealand, 2014 - Prince George excitedly meets a bilby, who is also named George after the little royal, during a visit to Sydney's Taronga Zoo.

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Happy birthday! - The family released this photo taken at the Natural History Museum in London on George's first birthday.

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Princess Charlotte's birth, 2015 - When Princess Charlotte was born in May 2015, William brought big brother George to visit her at the hospital.

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Princess Charlotte's birth, 2015 - Both George and his father waved to the crowds who had gathered outside the hospital, waiting for the birth of the little princess.

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Trooping the Colour, 2015 - George and William were next seen at the Trooping the Colour ceremony in June 2015.

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Polo match, June 2015 - William crouches to speak to his young son at a polo match in Gloucestershire.

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Princess Charlotte's christening, 2015 - The family made their first appearance as a family of four at Princess Charlotte's christening in July 2015.

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Princess Charlotte's christening, 2015 - While Kate pushed Princess Charlotte along in the stroller, William carefully carried George in his arms.

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Family ski holiday, 2016 - Early in 2016, Kate and William released pictures of their family on a ski vacation in the French Alps.

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Family ski holiday, 2016 - William supports his son while Charlotte sits happily in her mother's arms.

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Meeting Obama, April 2016 - Prince George nervously greets a very special visitor in his robe, while William looks on proudly.

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Air Show, July 2016 - The young Prince was carried by his father as the family watched an Air Show at RAF Fairford.

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Air Show, July 2016 - The three-year-old wore a pair of light blue earmuffs as his father led him across the runway.

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Canada Tour, September 2016 - It may be Charlotte's first royal tour, but George has done this before! William holds his son's hand as the young Prince waves to crowds in Canada.

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Canada Tour, September 2016 - Father and son share an adorable embrace.

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Christmas, 2016 - Kate carries Charlotte and William firmly takes George's hand as the family make their way to church on Christmas day.

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Christmas, 2016 - The young prince looked bored as he waited for his father to finish chatting outside St Mark's Church in Berkshire.

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Trooping the Colour, 2017 - Both William and Kate laugh at their son's obvious delight during the Trooping the Colour ceremony in June 2017.

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Trooping the Colour, 2017 - As George starts to look bored, William puts a comforting hand on his son's head.

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Poland and Germany, 2017 - It was a busy summer in 2017 for William, Kate, and their family. In July they made a royal tour of Poland and Germany.

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Poland and Germany, 2017 - The almost four-year-old prince looked tired upon arrival in Warsaw.

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Poland and Germany, 2017 - Prince William strokes his son's head as they land in Berlin.

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Poland and Germany, 2017 - Luckily the little prince was in better spirits as the family left Germany at the end of the tour.

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George's first day of school, September 2017 - One of the cutest father and son snaps is this one from George's first day at school.

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George's first day of school, September 2017 - William watches protectively as George shyly shakes hands with a teacher at his new school.

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Prince Louis' birth, 2018 - Prince William and the little royals walk into St Mary's hospital in London to meet their new baby brother.

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Prince Louis' birth, 2018 - William helps his kids up the steps on their way to see new Prince Louis on April 23, 2018.

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Prince Harry and Meghan Markle's wedding, 2018 - Both William and George had to get very dressed up for Uncle Harry's wedding to Meghan Markle in May 2018.

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Prince Harry and Meghan Markle's wedding, 2018 - The whole family were impeccably dressed for the happy occasion!

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Trooping the Colour, 2018 - The public appearance of the Cambridges in June 2018 at the Trooping the Colour ceremony. Both father and son seemed to be unaware of Charlotte's slip on the balcony!

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Trooping the Colour, 2018 - Kate and William looked stern as the royal tots played around with their cousin, Savannah Phillips.

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Prince Louis' christening, 2018 - While all eyes were on Kate and the newest addition to the family, Prince Louis, during his christening in July 2018...

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Prince Louis' christening, 2018 -

...it was William who gently led his son and daughter on the big day. What a cool dad!

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Trooping the Colour, 2019 -

The whole family looks up during the Trooping the Colour ceremony in 2019.

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George's first day of school, September 2019 -

This day marked Charlotte's first day in school, at Thomas's Battersea in London. 

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Match day, 2019 -

On October 5, 2019, the father-son duo took in the match between Norwich City and Aston Villa at Carrow Road Stadium.

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Christmas lunch at Buckingham, 2019 -

Father and son seen driving over for Christmas lunch at Buckingham Palace. 

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'Big Night In,' 2020 -

The family poses for a video for BBC Children In Need and Comic Relief's 'Big Night In.' This was in April 2020, as the UK was coming to grips with COVID-19.

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Euro 2020, 2021 -

Father, son, and mother celebrate England's first goal against Germany at London's Wembley Stadium. Euro 2020 was postponed to 2021 due to the COVID-19 pandemic.

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Trooping the Colour, 2022 -

Prince William was clearly entertained by the face George pulled as he strained to catch the astonishing aerial display at the Trooping the Colour ceremony in 2022.

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Wimbledon, 2022 -

It was a day out for the boys at the Wimbledon men's singles final in 2022!

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The Big Help Out, 2023 -

Prince William watched over George proudly as the young prince showed off his archery skills at an event with the Upton Scouts.

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The Big Help Out, 2023 -

During that same day, father and son found themselves behind the wheel of a digger for some hard graft! 

See also: Prince William: life in pictures

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