She Made It! Prince Harry Brings Meghan Markle as His Date to Pippa Middleton's Wedding Reception

Prince Harry brought girlfriend Meghan Markle to Pippa Middleton's wedding reception on Saturday, marking a major milestone in the couple's relationship

Prince Harry brought girlfriend Meghan Markle to Pippa Middleton’s wedding reception on Saturday, marking a major milestone in the couple’s relationship.

A source tells PEOPLE that Harry, 32, and Markle, 35, were both in attendance at the private evening reception.

As PEOPLE previously reported, Harry wasn’t planning on bringing Markle to the church ceremony between Middleton and new husband James Matthews earlier in the day. However, he was planning on bringing her to the larger (and more informal) post-church party at the Middleton family’s home in nearby Buckleberry that evening. A source told PEOPLE that Markle stayed in London (about and hour-and-a-half away from the ceremony in Englefield) during the church service and was going to be picked up by Harry after the morning service.

Guests had several hours between the church service and the evening party, leaving plenty of time for Harry to pick up Markle. Several guests were seen around town wearing black tie — men in tuxedos and women in glamorous frocks. Guests were chauffeured to the Middleton home in Range Rovers after they got checked by security at a separate location in town.

Samir Hussein/WireImage

Even though the pair has already attended a wedding together before (the Jamaican nuptials of one of Harry’s good friends), Meghan’s appearance at Middleton’s wedding — even if it’s just the reception — signals that she and Harry are getting very serious.

Kirsty Wigglesworth/AP

Several royal family members, including Prince William, Princess Kate and Princess Eugenie, were all in attendance at the nuptials at St. Mark’s Church in Englefield. Prince George and Princess Charlotte served as page boy and a bridesmaid, respectively — and they naturally stole the show!

James Matthews, Pippa Middleton and Kate Middleton. Kirsty Wigglesworth/AP

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Mark Cuthbert/UK Press/Getty; James Whatling/MEGA

Earlier this month, the couple was snapped sharing a sweet kiss and embrace after Harry’s charity polo match, marking their first public event together.

And in April, Harry flew out to Toronto (where Markle films Suits) to spend Easter weekend with his girlfriend — skipping the usual royal Easter tradition of attending services at St. George’s chapel at Windsor castle with Queen Elizabeth II.

“Despite the distance, the media attention and everything else, there’s a real ease to their relationship,” a source recently told PEOPLE. “It just works. They are deeply happy.”

• additional reporting by PHILIP BOUCHER