Pippa — the younger sister of Kate Middleton — is a longtime friend of the groom
James Matthews and Pippa Middleton
| Credit: Tim Rooke/REX/Shutterstock

Royal wedding déjà vu!

Pippa Middleton and husband James Matthews were back at St. George’s Chapel to celebrate Lady Gabriella Windsor’s royal wedding on Saturday. Exactly one year ago, the couple attended the nuptials of Meghan Markle and Prince Harry at the same location. They also attended the wedding of Princess Eugenie to Jack Brooksbank at St. George’s Chapel four days before giving birth to her first child in October.

Pippa, who welcomed her first child — a baby boy — in October, wore a belted floral blue dress for the happy occasion, which she paired with the “Classic Azure Headband” by Jess Collett Milliner. Adding to the glamour, the wide style headband was covered with powder blue silk velvet. Her husband also got the color memo, adding a matching blue vest to his wedding day ensemble.

Pippa — the younger sister of Kate Middleton — is a longtime friend of the groom, Thomas Kingston. Kingston, who works in frontier market investment, popped the question to Lady Gabriella, who is a senior Director at at Branding Latin America, on Sark, one of the Channel Islands just off the coast of France.

The bride’s parents, Prince Michael and Princess Michael, were “delighted” with the news, the palace said in a statement.

Also among the wedding party were Pippa’s parents Carole and Michael Middleton, as well as her brother James Middleton. Their royal sister Kate Middleton was not at the wedding, nor was Prince William, who is preparing to attend the soccer FA Cup final. However, Prince Harry did make a surprise appearance after welcoming son Archie Harrison with wife Meghan Markle on May 6.

Michael and Carole Middleton, James Matthews, Pippa Middleton and James Middleton
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Mandatory Credit: Photo by Tim Rooke/REX/Shutterstock (10239423k) Michael Middleton and Carole Middleton The wedding of Lady Gabriella Windsor and Thomas Kingston, St George's Chapel, Windsor Castle, UK - 18 May 2019
Michael Middleton and Carole Middleton
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Alizee Thevenet and James Middleton
| Credit: Tim Rooke/REX/Shutterstock

In April, Pippa opened up about being a first-time mom to baby Arthur.

“Starting my son Arthur swimming at four months old has given him confidence and enjoyment in water,” she wrote in Waitrose Kitchen magazine. “He’s now six months old, and swimming is one of our favorite activities. The exercise helps guarantee sound daytime sleeps, and the movement has improved his digestion.”

Pippa, 35, previously said swimming had become a go-to way to keep up her fitness routine as she neared her due date.

“From personal experience, I’d confidently say I find it has been the most enjoyable and rewarding form of exercise since I found out I was expecting,” she shared. “It’s comforting to know that it’s safe throughout pregnancy, and you don’t need to adapt and change too much (unlike most other sports). It’s so good for you that you could swim every day – as long as you don’t overexert yourself – right up until the end of the third trimester.”

Pippa Middleton and James Matthews at the wedding of Prince Harry and Meghan Markle on May 19, 201
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Princess Eugenie Of York Marries Mr. Jack Brooksbank
James Matthews and Pippa Middleton attend the wedding of Princess Eugenie and Jack Brooksbank
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Pippa and James have been spotted around London and on vacation in St. Barts since becoming parents, but she made her first official post-baby outing at a charity gala event in late February.

A source previously told PEOPLE that Pippa and James are looking forward to settling down and “having children and leading a quiet life.”