The Keeping Up With The Kardashians stars partied the night away at 1 OAK Nightclub at The Mirage Hotel & Casino on 22 February, marking their first public appearance together since the birth of son Reign Aston in December.
This also marked Kourtney's first public appearance at all since giving birth to little Reign on 15 December. And doesn't she look great?!
Kourtney, 35, wore all black for her night out, joking on Instagram that when in doubt about what to wear, go for all black!
She also revealed despite being in Sin City, she was sticking to non-alcoholic drinks and not planning to be away from her children for long. "About last night," she said. "Quickest middle of the night Vegas trip ever! Drank one too many cups of hot tea."
Kourtney was no doubt eager to get back to her kids in LA: baby Reign, two-year-old daughter Penelope and five-year-old son Mason.
So far, she hasn't revealed a picture of Reign's face, although she has teased fans by posting a photo to Instagram showing the baby's (very well dressed) lower half!
Come on, Kourtney! We want more!
Before heading to Vegas, Kourtney had been in snowy Montana with her sisters celebrating a friend's birthday.
Unfortunately, the family didn't have the best end to celebrations when a car Khloe was driving that carried Kim, Kylie and baby North veered off a road after hitting ice.
Thankfully, nobody was injured.
"We were in Montana," said Khloe. "I hit some black ice, the car span out of control. Like, a big rig had got ice all over the car and we couldn't see anything, so our car span out of control, but I gained control and ended up in a ditch. I was driving."
Why is Kourtney famous? Find out more in the video below!
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