Following the celebrations, the actress - who was previously in a relationship with Prince Harry - took to Instagram to share a rare selfie with her husband, Harry Wentworth-Stanley.
The snapshot was taken on a beach, with the couple happily posing together and keeping the bump away from view.
WATCH: Cressida Bonas arrives for the royal wedding
Cressida, 33, simply added a jumping heart GIF to the post. Cressida and her long-term love Harry tied the knot in a private wedding ceremony in July 2020 after announcing their engagement in August 2018.
The pair are believed to have met when they were both students at Leeds University; they briefly dated before the property developer left for a year abroad in Argentina.
During this time, the actress embarked on a two-year relationship with Prince Harry after they were introduced to each other by Princess Eugenie in May 2012.
Cressida and Harry cuddle up for their beach selfie
The former couple have remained on good terms since the end of their relationship, with Cressida among the guests at Harry's wedding to Meghan Markle in Windsor in May 2018.
It's believed Cressida and her husband were forced to cancel their original plans due to the coronavirus pandemic.
In January 2020, during an interview with ES Magazine, the star opened up about her initial wedding plans and how she wanted to keep her big day relatively low-key.
Cressida styled a pink pleated skirt to Lady Tatiana Mountbatten's wedding
"I won't have a huge wedding, that's not really us," she explained.
"We aren't traditional people, even though Harry [Wentworth-Stanley] proposed in a traditional way – I've never thought about how someone would propose to me. And I don't want a meringue dress. People look beautiful in them but I don't think I would."
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