What did you do this weekend? If you were Rob Kardashian, you could say you partied with your mom!

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Kris Jenner tagged along with her son when he celebrated his 26th birthday in Las Vegas on Friday night. Rob and Kris started the party at Stack Restaurant at the Mirage where they tossed back shots of Casamigos tequila during a 2 1/2-hour dinner.

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"At one point, Kris, who was sitting at her own table in the main dining room, came back to the private dining room where Rob and his friends were seated to do a toast," says an eyewitness.

The group then hit up 1 OAK Nightclub. And, of course, there was cake.

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Too bad Rob ended up wearing more of it than he ate since, says the eyewitness, "One of his friends smeared it on him."

After that, "Rob was singing and dancing along to the music," says a partygoer, who adds the crowd went wild when DJ Karma played Kanye West's song "Clique."

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"Kris posed with Rob for some photos and then she got on the mic to give him another birthday toast."

Is it cool or creepy that Rob partied with his mom? Tell us what you think in the comments below or on Twitter @OKMagazine

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