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Catherine Middleton is born on Jan. 9, 1982, in Reading, England, the eldest of three children of Carole, a former flight attendant, and Michael, a flight dispatcher. Fun fact: Middleton is christened at St. Andrew's Bradfield in Berkshire the day before her future husband is born.
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Princess Diana gives birth to William on June 21, 1982, the first child for her and Prince Charles. As a child, he was nicknamed Wombat, and he becomes a big brother two years later when Harry is born.
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The couple meet in 2001 at the University of St. Andrews in Scotland, but Middleton reportedly doesn't really catch William's eye until the St. Andrews Charity Fashion Show in March 2002, in which she models this see-through dress.
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The pair keeps their relationship on the down-low for a while, with Buckingham Palace always declining to comment. But they are outed as a couple after paparazzi snaps them skiing together in Switzerland in March 2004.
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The couple that graduates together stays together. William and Middleton receive their art history degrees from St. Andrews on June 23.
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PDA alert! The two are captured in a rare moment of affection, when William goes in for a kiss after playing a soccer, er, football game.
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Who doesn't love a man in uniform? Middleton is front and center with Queen Elizabeth II to watch William receive his commission as an officer in the army at Royal Military Academy Sandhurst on Dec. 15.
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The couple takes in a rugby match with William's little bro. Why the face, Harry?
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Look at the matching tweed! William and Middleton attend the Cheltenham Festival, one of their last public appearances together before breaking up.
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Middleton heads to work in late April, weeks after reports surfaced that the couple had split. "We don't comment on Prince William's private life," Buckingham Palace says at the time.
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No hard feelings here. The two remain friends after their breakup, with Middleton and her family attending The Concert for Diana at Wembley Stadium to mark the 10th anniversary of her death. They do not sit together, however.
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After being seen together in public several more times, the two are officially back on by April 2008, when Middleton attends William's graduation ceremony from Royal Air Force College Cranwell.
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Middleton laughs it up with her future in-laws at William's induction into the Order of the Garter, along with other members of the royal family, on June 16.
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William and Middleton are all smiles as they leave a friend's wedding, which only fans the flames as to when they will walk down the aisle. It turns out, pretty soon!
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The couple announce their engagement on Nov. 16. William had proposed in October during a 10-day trip to Kenya with his mother's 18-carat sapphire-and-diamond engagement ring.
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William and Middleton make their first public appearance as a betrothed couple at a Christmas reception for the Teenage Cancer Trust.
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Never too soon to start the baby rumors! The pair greets children at the launch of the Royal National Lifeboat Institution's new lifeboat Hereford Endeavour.
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Stay dry, guys! The two goof off watching a tug-of-war match in Belfast, Northern Ireland. We don't know about you, but we never look this good — or stylish — standing in the rain.
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I do! William and Middleton marry on April 29, 2011, at Westminster Abbey in a ceremony attended by 1,900 guests. More than 300 million people watch the nuptials globally, with 26 million watching in Great Britain alone. After the wedding, Buckingham Palace announces that Middleton's formal title will be Catherine, Duchess of Cambridge.
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The newlyweds leave Buckingham Palace the next day to go on a 10-day honeymoon to the Seychelles.
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Coming to America! The Duke and Duchess' first official tour as a married couple brings them to North America. On their first leg, they visit Canada, including the Calgary Stampede. Needless to say, these cowboy hats don't rival anything they wear in England.
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The royal family boards the Spirit of Chartwell during Queen Elizabeth's Diamond Jubilee Pageant on the River Thames. This is only the second time in history that the U.K. has celebrated a monarch's 60-year reign.
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William and Middleton cheer on Team GB at the London Olympics. William's cousin, equestrian Zara Phillips, wins a silver medal in team eventing.
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Watch where your hands are! Middleton stirs pregnancy rumors when she's photographed with her hand over her stomach while visiting a community garden project in England.
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It's true! The couple announces their pregnancy on Dec. 3 after Middleton is hospitalized with acute morning sickness. She is discharged by the end of the week. The happy news is marred when a nurse, Jacintha Saldanha, commits suicide after patching a call through to Middleton's room from two Australian radio hosts who were pretending to be the Queen and Prince Philip.
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The world gets its first royal baby bump sighting when Middleton visits Hope House, an Action on Addiction women's treatment center, in London.
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The parents-to-be attend a St. Patrick's Day Parade at Mons Barracks in southern England. William is there as the Parade Colonel of the Regiment, while Middleton presents the traditional sprigs of shamrocks to the officers. Meanwhile, reports surface that the two are expecting a baby girl; Buckingham Palace does not comment.
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William and Kate are Pot-heads! As in, Harry Potter fans. They couple casts a spell with their wands on an old Harry Potter film set at the opening of Warner Bros. Studios Leavesden in London.
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A glowing Middleton attends a garden party at Buckingham Palace with soon-to-be grandparents Prince Charles and Camilla.
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Bring on baby! William and Middleton make their last official public appearance together before the royal baby's birth at the annual Trooping the Colour Ceremony at Buckingham Palace on June 15.