Kim Kardashian showed off her incredible body in a new bikini pic on Instagram. The reality star posted a photo of herself in a black string bikini in front of her bathroom sink, bragging that she was wearing sister Kylie Jenner's suit.

"Quick swim before the Dash party!" she captioned the first photo. In a second shot she wrote: "Yep stole Kylie's bikini...she's not getting it back."

Perhaps Kardashian felt like she had to prove that she can squeeze her 30-year-old body into her 16-year-old younger sibling's swimwear. Well, she did it!

Last month, Jenner showed off her bikini body in a similar two-piece bathing suit. "So… is it summer yet?..," she wrote.

After posting her selfie, Kardashian attended the grand opening of DASH Miami Beach with sisters Khloe and Kourtney. She wore an unusual, see-through metallic ensemble that showed off her midriff.