The pair tied the knot on April 29, 2011, at Westminster Abbey in London. A million people lined the city streets, hoping to catch a glimpse of the couple, while many more around the world watched the day unfold on TV.
“You could hear it all outside to begin with as she approached,” Martin Fidler said of the royal wedding entrance. “It was like a wave of sound getting louder and louder as she got closer to the Abbey. When the trumpets started inside to announce that she’d arrived, it’s a wonder the roof didn’t lift off!”
The college sweethearts met while they were students at the University of St. Andrews in Scotland in 2001. During their second year, they shared a townhouse with two other friends. It wasn't until 2003, though, that the pair reportedly began dating. They were able to keep their relationship hush-hush until they were photographed together on a ski trip in 2004. (Kate is pictured here on their graduation day in June 2005).
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The couple sneaks a kiss after a March 2006 sporting event at Eton College, the boarding school the prince attended as a teen.
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Things are getting serious! Then-girlfriend Kate attends the wedding of William's stepsister Laura Parker Bowles in May 2006.
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Kate spends time with William and his brother, Prince Harry, while cheering on England at a February 2007 rugby championship match.
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After a brief breakup in the spring of 2007, William and Kate (seen here sitting in first and third rows, respectively) reunite at the Concert for Diana at Wembley Stadium on July 1, 2007 — which would have been the late Princess Diana's 46th birthday.
William and Kate attend the October 2010 wedding of their friends Harry Meade and Rosie Bradford in Northleach, England.
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The future Duke and Duchess of Cambridge officially announce their engagement in November 2010. William proposed during a trip to Kenya the month prior with a sapphire and diamond engagement ring that had belonged to his mother, the late Princess Diana.
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The couple wave to well-wishers after attending a naming ceremony for a new royal lifeboat in February 2011. It was their first official appearance after the announcement of their engagement.
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The pair return to the University of St. Andrews — where they first fell in love — to help launch a scholarship in their honor in February 2011.
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The new Duke and Duchess of Cambridge smile following their royal wedding ceremony at Westminster Abbey on April 29, 2011.
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A month after their nuptials, Will and Kate meet with then-President Barack Obama and first lady Michelle Obama at Buckingham Palace in May 2011.
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A growing family! The Duke and Duchess of Cambridge welcome their first child, Prince George, in July 2013. He is third in line to the throne behind his grandfather Charles and father William.
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Nearly two years later, on May 2, 2015, the couple welcome their second child, Princess Charlotte. She is fourth in line to the throne behind her older brother, George.
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And then there were five! On April 23, 2018, Kate gives birth to another boy. Their third child, Prince Louis, is fifth in line to the throne.