Kourtney Kardashian, 38, flaunts her impressive curves as she rocks a tiny black string bikini

With Kourtney Kardashian's fit figure, it is quite unbelievable that the reality TV star has given birth to three children.

While on a vacation with her sister Kim, she shared numerous photos of her in bikinis which showed off her smoking physique.

In one photo, she showed off not just hers, but her sister's incredible bodies as they walked along the shorline of the beach they were in.

All the hardwork the Kardashian sisters have put in the gym and in dieting has worked wonders given the shocking results.

Kim sported a hot pink bikini and orange mirrored shades, while Kourtney donned a black mini-bikini and matching sunnies

during their Turks and Caicos getaway.

In a now deleted photo, Kim posted a photo of the two sisters sitting back-to-back in matching black bikinis, sunnies, and visors.

The caption wrote #nationalsiblingsday, but realizing her other siblings would probably feel left out, the beauty mogul deleted her snapshot after a few hours.