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THE LITTLE PRINCE
Six months after his June 21, 1982, arrival, Prince William poses for what would be the first of many snapshots with his mother, Princess Diana, in December at their London royal residence, Kensington Palace.
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A year later, William smiles brightly for the cameras while roaming the home's garden on Dec. 14 during his first official photo call. "He has the good fortune not to look like me," his father Prince Charles once said.
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Two years old and towheaded, William takes a seat on his mother's lap for a portrait session in May 1984.
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Uh-oh, someone's not happy! The newly minted big brother shows his displeasure at having to share toys – and the spotlight – with Prince Harry (born September 15, 1984) while being photographed in their Kensington Palace playroom in October 1985.
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He's got his future all figured out! Twenty years before joining the military, William dons the camouflage attire and burgundy beret of the Parachute Regiment during a 1986 summer trip to Highgrove House, the royals' country estate in Gloucestershire.
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Already beginning to embrace public attention, the dapper prince, 5, greets royal watchers with the "Windsor wave" as he exits Christmas service at St. George's Chapel in 1987 with cousins Zara and Peter Phillips.
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William happily wraps his arms around his mother while sitting for a family portrait to mark dad's 40th birthday in August 1988. The young prince would come to serve as Diana's "chief comforter" during her rocky marriage to Charles.
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DOG DAY AFTERNOON
Long before Lupo entered the picture, the 6-year-old shows off his enduring soft spot for animals at the Minchinhampton horse trials in May 1989.
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A GRAND RIDE
What a view! The prince takes in London from aboard a carriage ride with his mother, brother and great-grandmother, The Queen Mother, on June 16, 1990, during the Trooping the Colour parade, which honors the British army and marks the sovereign's birthday.
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ON THE WATERFRONT
William and Harry join their mother on one of many family excursions: a trip to Canada, where they don waterproof capes for an October 1991 boat tour of Niagara Falls.
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He's not quite the right height yet, but 10-year-old William proves he's already got a need for speed, taking a seat behind the wheel at the British Formula 1 Grand Prix in July 1992.
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Following Princess Diana and Prince Charles's separation in December 1992, William and Harry's time with mom centers on age-appropriate events like visits to Britain's Thorpe Park in 1993, where a soaked William flashes an ear-to-ear grin.
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SHOW & TELL
Sitting between his estranged parents, 12-year-old William learns how to represent the royal family at events, such as an August 1994 celebratory parade marking Victory over Japan Day. "William is being taught how to behave in public," royal watcher Brian Hoey said of the young prince.
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Say Swiss cheese! The eldest Windsor plays protector, looking after Harry and Princesses Beatrice and Eugenie while photographers clamor for a photo during a January 1995 family vacation in Klosters, Switzerland.
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COMING UP ROSES
How sweet! At 14, the prince gets treated to a bouquet from a member of his admiring public after attending Christmas Day service at Sandringham Church in 1996, the same year British tabloids begin dubbing him "Prince Dreamboat."
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WILD AT HEART
It's an all-boys bonding moment for William, Harry and Prince Charles while out exploring the grounds of Balmoral estate with their dogs, Labrador Widgeon and Jack Russell terrier Tigga, on Aug. 10, 1997. But only three weeks later, the family would be struck by tragedy with the unexpected death of Princess Diana.
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While on vacation with his brother and father in Vancouver, Canada, on March 24, 1998, William works the crowd like a pro for his first set of appearances since Diana's death. "He has some of his mother's magic with people," says his uncle Earl Spencer.
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While the boys are as different as can be, "William looks after Harry," a family friend says of the pair, who sport matching sweaters while catching up at Highgrove in July 1999. "[They] have got much closer [since entering Eton College]."
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MIND THE GAP
After graduating from Eton, William spends his 18th year abroad, traveling to Chile in December 2000 to work on construction projects in the South American town of Tortel. His devotion to giving back is something Diana had hoped to impress upon her sons, saying, "I want them to have an understanding of people's emotions, of people's insecurities, of people's distress, of their hopes and dreams."
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In September 2001, William takes a rare moment to speak with the press before beginning his term at Scotland's St. Andrews University, asking for privacy from the media so that he can blend in with the other students. "It will get easier as time goes on," he says of the attention. "Everyone will get bored of me."
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TWO OF A KIND
Like father, like son! Twenty-year-old William wraps a loving arm around his father during their annual ski vacation to Switzerland in March 2002. "He's emerged as a very successful single parent," says Hoey of Charles.
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In May 2003, William makes time for some fun while at St. Andrews, where he studies art history and geography and begins dating future wife Kate Middleton. "I'm not a party animal, despite what some people might think," he says. "But I like to go out sometimes like anyone else."
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GUEST OF HONOR
Hope he didn't upstage the groom! The prince cuts a fine figure at the wedding of childhood friend Edward van Cutsem – who would later return the favor – and Lady Tamara Grosvenor on November 6, 2004, at Chester Cathedral.
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Following his June 2005 graduation from St. Andrews, William enjoys a brief respite in New Zealand, where the accomplished athlete gets in a game of rugby with members of the professional team the British and Irish Lions.
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AT EASE, SOLDIER
William can't help but crack a smile as his grandmother, Queen Elizabeth II, inspects him and his fellow graduates from the Royal Military Academy in Sandhurst, England, on December 15, 2006. His completion makes him a member of the Household Cavalry's Blues and Royals.
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RIDING THE WAVE
The boys get into the groove at the July 1, 2007, Concert for Diana, a special celebration of their late mother's life on the 10th anniversary of her death and what would have been her 46th birthday. "This evening is about all that our mother loved in life – her music, her dance, her charities and her family and friends," William says to the crowd at London's Wembley Arena.
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SPORTING GOOD TIME
William teaches one lucky pint-size pal about fandemonium when he visits St. Aidan's Primary School in Blackburn, England, on May 9, 2008, as part of his duties as president of the English Football Association.
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BAND OF BROTHERS
Together again, the princes sync up for a photo call at Royal Air Force Shawbury, home of the Defence Helicopter Flying School, where William trains to become a Royal Air Force search-and-rescue pilot and Harry prepares to join the Army Air Corps.
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At the ready! William swaps his military uniform for that of a cricketer, playing in a friendly game on behalf of the King's Head Inn on July 17, 2010, in Chipping Norton, England.
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OFF THE MARKET
After nearly nine years together, William weds Middleton – now known as the Duchess of Cambridge – on April 29, 2011, at Westminster Abbey, from which the couple emerges as man and wife.
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A day after his son's July 22, 2013, birth, William carries newborn baby George. Later that day, he strapped him into his car seat next to mom Kate. In an interview a few months later, William expressed how important it was for him to drive his family home from the hospital.
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Nine months later, William and Kate set off for a royal tour of Australia and New Zealand. Making the trip all the sweeter, Prince George tags along – just like William did with his parents when he was George's age.
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THREE BECOMES FOUR
June 21, 2015 is extra-special for William for many reasons: not only is it his 33rd birthday, but it's also his first Father's Day as a dad of two. Nearly two years after Prince George's birth (and almost 33 after his own!), the prince returns to the steps of the Lindo Wing at St. Mary's Hospital to debut his baby daughter, Princess Charlotte.
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Will, Kate, George and Charlotte have had quite the year as a family of four – including a snow-filled trip to the French Alps. He'll also start off his 34th year away from home, in the French city of Saint Etienne, where he's watching a soccer match between England and Slovakia. He'll head home that morning to celebrate "privately."
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William's 34th year saw him open up about being a parent, the early loss of his mother and more, particularly, in support of Heads Together, the mental health initiative he heads up along with Princess Kate and Prince Harry. It was also his last as an air ambulance pilot. He's retiring from the job and transitioning to full-time royal status later this year.
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