The momager, 59, is giving her Kardashian daughters a run for their money

By Michele Corriston
Updated August 29, 2015 11:00 AM
Credit: Brian Prahl/Splash News

It’s getting harder to keep up with Kris Jenner.

The momager, 59, is giving her daughters a run for their money in new photos from the family’s trip to St. Barts last week. Jenner – a grandmother of four! – showed off her enviable body in an itty-bitty black bikini and sheer loose cover-up while walking along the beach.

“After I have a coffee, I get myself to the gym in Beverly Hills, where I work out with Gunnar Peterson,” Jenner said of her 5 a.m. exercise routine in the September issue of Haute Living New York. “I end my day at 5 or 6. I used to work into the night, but learned that is unhealthy, and I wasn t feeling as productive the next day.”

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Jenner and her daughters Kim Kardashian West, Kourtney Kardashian, Khloé Kardashian, Kendall Jenner and Kylie Jenner (plus Kylie’s rapper boyfriend Tyga) vacationed on the Caribbean island together, posting a barrage of sultry swimsuit selfies during their stay.

The reality stars are back in Los Angeles now, and Jenner must have been pretty wiped out from traveling: She was caught sleeping on son-in-law Kanye West‘s shoulder at Khloé’s basketball player boyfriend James Harden’s lavish yacht birthday party Tuesday.