If you have a brother or sister then you know all about a good sibling rivalry.
It appears that Kendall Jenner and her sister Kourtney Kardashian might have a little Instagram rivalry -- and thank God for that.
Kendall posted a photo posing in a very small bikini while hanging out in the snow.
That photo was posted at 5:43 p.m. on December 29.
A day later, Kourtney posted a very similar set of photos but hers was even more revealing as she showed off her thong bikini.
Well, maybe it isn't really a rivalry as Kourtney did caption her photo, "Copied Kendall."
Kourtney got 4.4 million likes, Kendall received 7.4 million likes. Looks like Kendall won the competition.