Kourtney Kardashian wears "granny panties".

Kourtney Kardashian

Kourtney Kardashian

The 37-year-old reality TV star's sister Khloe revealed Kourtney's choice of underwear in a new post on her website, khloewithak.com.

She wrote: "I don't have period panties; I only wear thongs. Kourtney does, though! She'll show up to a workout and I'm like, 'Kourtney, are you wearing full granny panties?'"

And Khloe, 32, also revealed she never wears strapless bras.

She said: "I actually never wear strapless bras. I just don't get them because I feel like they don't stay up. I'd rather just wear a bra with the clear f**king straps attached, LOL!

"Lately, I've been obsessed with lacy bras and bralettes. My favourites are from For Love & Lemons, Are You Am I, Forever 21 and Anine Bing. Gooseberry Intimates makes my fave sexy bodysuits. It's the brand I wore to my Good American event at The Grove in LA."

And when it comes to underwear, Khloe takes advice from her mother Kris Jenner.

She said: "Kris Jenner's number-one piece of advice is to always wear matching bras and underwear because you never know who's going to see it. Words to live by!"

Khloe is currently enjoying a romance with basketball player Tristan Thompson, 25, but admitted when she doesn't have a partner she likes nothing more than discovering her own "individual identity" and doing whatever she wants.

She said: "Being single can be great. It can be a time to rediscover yourself, dedicate precious time to being selfish and enjoying your freedom!

"It's good to be single so that you can find your individual identity again. When you're with somebody for so long, there's a transition from being part of a couple to being single, but you need to gather yourself back together again without depending on anyone else. You are truly who you are when you are alone!"

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