The trio were joined by Pippa Middleton and her boyfriend Nico Jackson and James Middleton and his partner Donna Air and they all watched on as Charlie Gilkes said his 'I dos' with Anneke von Trotha Taylor.
Harry, who has just celebrated his 30th birthday, was looking completely dapper and arrived all suited and booted.
We couldn't help but notice Cressida Bonas wasn't at the wedding, even though rumours suggest she's dating Harry again (the pair went to a cinema in West London to watch Cameron Diaz's new flick Sex Tape).
The Duchess of Cambridge's sister Pippa was looking pretty in pink and wore a colour block pink and purple floaty frock by Tabitha Webb. The designer is a favourite of Pippas and she's been spotted wearing her dresses several times in the past. Kelly Brook's also been known to rock a few Tabitha Webb dresses in her time.
Harry's attendance at the wedding came at the end of a busy couple of weeks for the Prince who has been heavily involved in the Invictus Games in London.
He's also been celebrating his 30th birthday. He spent his birthday at Clarence house partying with 30 of his closest friends. The evening was ski themed and the palace was turned into a ski-lodge style nightclub.
Sadly, his sister-in-law Kate, who organised much of the evening, was unable to attend because of the morning sickness she's been suffering from while pregnant with her second child.
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