The Duke of Sussex may not have been his brother Prince William's official best man, but he still performed all the expected roles alongside Princess Kate's bridesmaid Pippa Middleton.
After the Prince and Princess of Wales exchanged vows at London's Westminster Abbey on 29 April 2011, they made their way down the aisle as husband and wife, followed by their bridal party. The bridesmaids included Prince Edward and Duchess Sophie's daughter Lady Louise Windsor, aged seven, and Princess Margaret's granddaughter Lady Margarita, eight, who wore white puff sleeve dresses with green sashes.
Behind them, Pippa looked stunning in a figure-hugging McQueen bridesmaid dress as she linked arms with Prince Harry, who wore his black military uniform. Despite the fact that 1,900 guests were watching them in person – not to mention another 17.6 million on TV – Harry took the opportunity to share a private joke with Pippa, who couldn't contain her smile.
Kate met Prince William while they were both studying at St Andrews University and they dated on and off for around eight years before announcing their engagement in November 2010.
SEE: Princess Kate's twinning bridesmaid photos with sister Pippa aged 9 divide fans
William proposed with his late mother Princess Diana's sapphire and diamond engagement ring during a holiday with friends in South Africa, and he admitted he was so nervous that he didn't even speak to Kate's father Michael until afterwards!
He explained during their engagement interview with journalist Tom Bradby in 2010: "Well, I was torn between asking Kate's dad first and then the realisation that he might actually say 'no' dawned upon me.
"So I thought if I ask Kate first then he can't really say no. So I did it that way round." The royal added: "I managed to speak to Mike soon after it happened really and then it sort of happened from there." Meanwhile, Kate said she had "an awkward situation" when she caught up with her mother Carole, as she wasn't sure if she had heard the news.
For their wedding in 2011, the Princess looked gorgeous in a lace Alexander McQueen wedding dress that featured the designer's signature corset and full skirt, while William wore his red Irish Guards uniform, which was his most senior military position.
However, Harry said in his book Spare that the late Queen Elizabeth had been the one to make the decision about the groom's outfit, which left him "gloomy" and "frustrated."
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