Kourtney Kardashian Pumps Boobs Before Birthday Bash

Kourtney Kardashian celebrated her 31st birthday in Las Vegas this weekend with sisters Kim Kardashian and Khloé Kardashian Odom. But before Kourt could get down to celebrating — at a pool party held in her honor at Wet Rebulic at the MGM Grand Hotel/Casino— she had some boob business to take care of.

"Right before we walked down, Kourt was pumping her boobs to make sure the milk wouldn't start leaking at the party!" Kim told E! News about how things have changed for Kourt since the arrival of baby Mason Dash Disick.

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Mason and his daddy Scott Disick didn't attend Kourtney's Sin City pool party; however, Scott planned a special weekend for his baby momma.

"Scott surprised me and we went to Santa Barbara and had a little away time," Kourtney told E!.