Kylie Jenner just revealed who her 'favorite sister' is -- and, no, it's not Kendall

Kylie Jenner Kisses Hailey Baldwin and it Gets Emojified
Kylie Jenner Kisses Hailey Baldwin and it Gets Emojified

OMG! Kylie Jenner just revealed who her favorite sister is, and it's not the one who you'd expect.

The 18-year-old social media maven grew up alongside her slightly-older sister Kendall, but on Monday, Kylie called another one of her famous siblings her "favorite sister."

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So, who's her favorite? Kourtney!

That's right, in a sweet birthday message that Kylie posted on Monday, she dropped the unexpected bombshell about her preferred sis.

"I love you Kourtney," she wrote in the caption of a hilarious face-swap video. "You already know you are my favorite sister these days."

Okay, to be fair, she did say "these days," but it's still a big admission! I mean, come on, how would you feel right now if you were Kim, Khloé or Kendall? Definitely a little bit jilted.

See photos of Kylie Jenner through the years:

"Thank you for teaching me to see the glass half full through everything," she continued. "Happy birthday <3"

Kylie made headlines this past weekend for her daring outfits at Coachella that included a Louis Vuitton bathing suit, rainbow braids and peach hair, to name just a few elements of her memorable ensembles.

Kourtney is currently in Iceland celebrating her birthday alongside her sister Kim, her husband Kanye West and a few friends, including Simon Huck and Jonathan Cheban.

See photos of Kylie Jenner's various Coachella looks:

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