Khloe Kardashian and Kylie Jenner Do Water Cheerleading in Greece: GIF

Khloe Kardashian and Kylie Jenner do cheerleading in the water in Greece during a family vacation on April 29. Brian Prahl/Splash News

Khloe Kardashian and Kylie Jenner have got spirit! On the last day of their family vacation to Mykonos, Greece, the stepsisters got a little silly and decided to try out their cheerleading skills in the chilly water on Apr. 29.

"Kylie told Khloe, 'YOLO!' as in 'You only live once,'" an onlooker explained to Us Weekly of the girls' impromptu cheerleading routine.

Kardashian, 28, wearing a black tank top and long black shorts, gave her 15-year-older a lift on her back. Jenner, wearing a bikini top and jean shorts, then stood up tall and raised her arms in the air. She was quickly caught on camera in her perfect cheerleading pose, but didn't exactly stick the dismount. Instead, Jenner fell off Khloe's back in the water with a big laugh.

"I had the most magical time in Greece!" Khloe tweeted that same day. "All that was missing was [brother] Rob and my hubby [Lamar Odom]!! I missed them like crazy! Back in Cali heading to my boys."

But once she got home, she started planning a trip back. "Just finished telling Lamar about our trip to Greece! I still can't get over how stunning it is there," she tweeted later that night. "I can't wait to go back with my hubby."

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