Kourtney and Kim Kardashian are living it up in Punta Mita, Mexico with gal pals, in honor of Kourt鈥檚 birthday. While everyone looked smokin鈥 in their respective swimwear, it was Kourtney in an itsy bitsy, teenie weenie red string bikini that stole the show.

KOURTNEY MARY KARDASHIAN 馃槏馃敟馃敟馃敟 #kourtneykardashian

A post shared by Kourtney Kardashian (@kourtneylovely) on

The mom of three wore a Minimale Animale The Lucid Bikini Top ($85) that barely kept her covered. She鈥檚 showing a *lot* of underboob. Considering her top is a string bikini that she could have adjusted on her own, it seems like this is an intentional styling method.

Trend or not, the 38-year-old is definitely pulling this tough look off. She even complemented it with a pair of red circle shades and a simple gold cuff.

KK 馃敟馃敟馃敟 #kourtneykardashian

A post shared by Kourtney Kardashian (@kourtneylovely) on

Kourtney was also spied pulling off the same look in a black bikini while she lounged on a yacht. We鈥檙e definitely sensing a theme here.

Meanwhile North and Saint鈥檚 mom Kim wore a printed vintage Dior bikini with green, yellow, and red trim that she accessorized with layers of necklaces, huge hoop earrings, and Pucci sunglasses. There鈥檚 no underboob here, so perhaps its just a Kourtney trademark.

Who knows if Kourtney鈥檚 look will actually take off as a trend, but hey, it鈥檚 her birthday and she can wear what she wants!

What say you? Yay or nay? Let us know on Twitter @BritandCo.

(h/t Refinery29; photo via Kevork Djansezian/Getty)