On Thursday night, Kourtney Kardashian was a birthday girl living in a star-studded world.
In celebration of her 40th birthday, the Poosh mogul and mom of three spent the night surrounded by all of her famous family and Hollywood pals at a glamorous bash thrown in her honor.
All of the guests were dressed to impress, including both Kourt and sister Kim Kardashian, who donned black vintage Versace looks for the occasion. The star also poked fun at her sister’s famous insult with “Most Interesting to Look At” inscribed on bottles of Don Julio for guests, along with an etching of the birthday girl’s face. Of course, sisters Khloe Kardashian, Kendall Jenner and Kylie Jenner were in attendance as was matriarch Kris Jenner and grandma Mary Jo Campbell.
There was also no shortage of guys at the party, including Kim’s famous husband, Kanye West, French Montana, Jonathan Cheban, Kourt’s ex Scott Disick, and even her former flame Younes Bendjima, who not-so-subtly revealed his attendance at the soirée by posting a photo of the napkins on his Instagram Story.
Underneath a sparkling ceiling of lights, there was also no shortage of dancing as guests grooved while musicians played. When it came time to commemorate the special day, Robin Thicke and Siadid the honors with “Happy Birthday” harmonies, finished off with a cake in the shape of Kourtney nude sitting on the edge of her bathtub.

Her New Slogan
Poking fun at Kim Kardashian‘s past insult of her, Kourtney’s party featured these comical favors.

Journey to the Past
Who can forget what Kourtney told sister Kim Kardashian after she cried about losing her diamond earring in the ocean? The star had a little fun with her famous quote and put it on some of the napkins.

Bendjima Is Back
Kourt’s ex-boyfriend was a guest, as evidenced by a photo he posted of a napkin at the soirée.
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A Scott Sighting
Another famous ex, Scott Disick, was also in attendance along with his girlfriend Sofia Richie.

Kourtney and the Guys
The birthday gal posed with a group of her male guests, including Robin Thicke, French Montana, Kanye West and recently rumored beau Luka Sabbat.

Hi Paris Hilton
The socialite and longtime Kardashian friend was one of the many celebrity guests at the big bash.
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A Robin Thicke Serenade
The five-time Grammy nominee sang “Happy Birthday” for the guest of honor along with Sia.

A Sia Surprise
If you don’t recognize her without her signature wig, songstress Sia harmonized with Thicke for a “Happy Birthday” duet.

A Happy Birthday Indeed
The birthday star was clearly happy as she smiled from ear to ear in a black vintage Versace design.
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A Sultry Treat
The mom of three rang in her birthday with a very sexy sweet treat: a cake with a model of herself in the bathtub.

Three Generations
Kim Kardashian posed with the matriarchs of the Kardashian family, mom Kris Jenner and grandmother Mary Jo Campbell.

Kylie Kouture
The youngest of the sisters sparkled in a rhinestone bandeau and matching skirt.
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Versace Vibes
The reality star dressed up in a vintage Versace little black dress circa 1997 for her sister’s birthday.
Needless to say, we don’t think Kourt will ever forget this party.
Happy Birthday, Kourtney!
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