Kendall Jenner and Kourtney Kardashian Pose in Sexy Bikinis for 'Low-Key' Memorial Day Weekend

Kamp Kourtndall is in session — but the required attire is a little different from the average summer camp uniform.

Kendall Jenner and Kourtney Kardashian spent their Memorial Day at the pool, showing off their summer-ready figures in sultry bikinis.

A photo shared by Kourtney on Instagram — also featuring Kylie Jenner’s BFF Jordyn Woods and half of the musical duo Simi and Haze holding water guns — showed off the siblings’ two-piece suits. Kourtney, 39, opted for a simple pink bikini while Kendall, 22, rocked an appropriately patriotic red and blue number.

The sisters also modeled their looks for the kick-off to the summer season on pool rafts that resembled jet skis. “Low key,” Kourtney captioned the shot.

Kendall later shared the sun with another pal: her Doberman Pinscher. The model covered her face as she soaked up some rays with her furry friend by her side on a poolside lounge chair.

“Cute but she’ll rip your face off,” she warned of her pet in the caption.

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Kourtney’s holiday weekend included another pool-ready look as well. On Sunday, she shared a photo of herself tanning in a black bikini with a drink in hand. She paired the suit with sunglasses and a baseball cap.

But bathing suits weren’t the only attire for the long weekend: athlesiure gear was also required.

Kourtney shared videos from her exercise session with Kendall and other pals on Monday morning, proving that the ladies take no days off.