Kim and Kourtney Kardashian Rock Colorful Bikinis During Beach Day With Gal Pals -- See the Pics

The sisters were all smiles while hanging with friends in Tulum, Mexico.

Kim Kardashian West and her sister, Kourtney Kardashian, left the kids and the men at home, and hit the beach with their girlfriends.

Just a week after Kourtney celebrated her 38th birthday, the sisters jetted off to Tulum, Mexico, and were spotted wearing some seriously sexy bikinis while playing in the waves with their pals. Kim, 36, sported a vintage logo bikini by Christian Dior that she accessorized with large hoop earrings and gold reflective sunglasses.


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As for Kourtney, the mother of three wore a small bikini top and matching bottoms along with a gold bracelet. The Keeping Up With the Kardashians stars were joined by their bikini-clad pals Brittny Gastineau, Larsa Pippen and Kim's personal assistant, Stephanie Sheppard.


One swimsuit Kim doesn't appear to have packed for the trip is the bedazzled string bikini that she modeled last week. The mother of two shared several videos on Snapchat of herself posing in a dimly lit room while J. Holiday's song, "Bed," played in the background. She later took down the posts.

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Here's a look at that super skimpy bikini: