Pippa Middleton shows off her baby bump at Spencer Matthews' 30th birthday

34-year-old Pippa Middleton is not allowing her pregnancy to slow down her party roll. Dressed in a mint green polka dot dress that gracefully highlighted her baby bump, she and husband James Matthews attended the bash in the London flat earlier this week on Sunday.

Pippa's brother-in-law Spencer in the hit show Made in Chelsea and actually reached 30 years of ages on August 6th. Wife of Spencer, Vogue Williams, who accompanied her actor husband to the celebrations is also due for her first child this October. Her child and that of Middleton's will thus be cousins.

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Pippa's fashionably casual outfit was topped off with a pair of white sneakers and a brown cross-body purse. The shoes may be more suited to a tennis course outing, which she attended back in July, but worked just as well tying in with her comfy but classy outfit.

At the party, other guests in attendance included Oliver Proudlock, Hugo Taylor, Millie Mackintosh, and Jamie Laing, all former cast members of the Made in Chelsea show.

The pair, who have already been together for over a year, did not forget to bring along their dogs as well, a black spaniel, and a black labrador.

Rounding up the guest list, David Matthews, father of Spencer and James, made an unusual appearance despite the ongoing allegations of rape made against him. Emerging for only the second time in four months, David has so far strongly denied any accusations. French authorities are in charge of the ongoing investigation.

During the party, guests seemed to be having a pretty good time. At one point, Spencer is photographed sharing laughs, cheery conversation, and passing a friendly hand on Pippa's cheek.

All in all, the sister to the Duchess of Cambridge still appears in good health. She did not endure nearly as much in her first trimester as her sister did with all three of her children. She also detailed her changed workout habits in her online health column.

Her expected little one may not inherit a royal title for this reason, but they will surely experience the high life.

And Pippa, who was hesitant at first to announce her pregnancy to the public, confidently continues on the move before the delivery.