Kourtney Kardashian's 40th Birthday Party: Take a Look Inside the Celebration

The hosts

Kourtney's bash was hosted by her mom, Kris Jenner, sister Khloé Kardashian and brother-in-law, Kanye West. Rules for the party, as previously told to Jimmy Kimmel by Kourtney, included "No speeches, mom is not allowed to cry, if my mom cries I have to somehow shuttle her out, and we're not allowed to say what age it is. No balloons."

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Kardashian Sisters

A post shared by Kim Kardashian Snapchat 🍑 (@kimkardashiansnap) on Apr 19, 2019 at 5:31am PDT

The family

Along with Jenner, West and Kardashian, the rest of Kourtney's family, including grandmother Mary Jo, sisters Kim Kardashian, Kylie Jenner and Kendall Jenner were all on hand to celebrate. Scott Disick, the father of Kourtney's three kids, was also at the bash.

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Kylie last night at Kourtney’s birthday party

A post shared by Kim Kardashian Snapchat 🍑 (@kimkardashiansnap) on Apr 19, 2019 at 5:45am PDT

The guests

Robin Thicke and Sia were on hand to serenade Kourtney with their version of "Happy Birthday," while Kourtney's ex Younes Bendjima was also spotted, as was Khloé's ex French Montana. Other celebrity guests included Paris Hilton and Kylie's boyfriend, Travis Scott.

The decor

Last year, Kim made headlines for slamming her sister as the "least interesting to look at," a phrase repurposed for the party with "most interesting to look at" engraved on liquor bottles along with an image of Kourtney's face.

The phrase was also printed on napkins at the party, as was one of Kourtney's most famous Keeping Up With the Kardashians quotes — "Kim, there are people that are dying."

The dress

For her party, Kourtney donned a black Versace dress with sheer paneling, making her grand entrance to the bash while holding daughter Penelope's hand as sparklers lit up the path and a saxophonist serenaded the duo.

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Yes Kourtney!

A post shared by Kim Kardashian Snapchat 🍑 (@kimkardashiansnap) on Apr 18, 2019 at 11:05pm PDT

The cake

No birthday party would be complete without cake, and Kourtney's was a miniature version of the reality star sitting naked on the edge of a bathtub surrounded by beauty products, clothes and champagne bottles, with the bath tiles reading, "Happy Birthday Kourtney!"

Photo Credit: Getty / Axelle/Bauer-Griffin