Kylie Jenner and Kourtney Kardashian might be releasing a makeup collab
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Clearly, Kylie Jenner likes to keep it all in the family: She's already teamed up with older sisters Kim and Khloé Kardashian for must-have Kylie Cosmetics collections, and with Kendall Jenner on multiple fashion lines. The only sister she hasn't worked with is Kourtney Kardashian, but, if eagle-eyed fans' suspicions are correct, a Kylie x Kourtney collab could already be in the works.

As Stylecaster first reported, Twitter user LaRonda Mangum spotted what appears to be a clue as to which sister will team up with Kylie next in last Sunday's episode of Keeping Up With the Kardashians. On Monday, LaRonda tweeted a photo of a random shot from the episode in which four Kylie Lip Kit tubes sit on a table next to another lip gloss container clearly emblazoned with Kourtney's name. "What is this future blessing that I see in the background?!ūüėć Another collab featuring @kourtneykardash in @kyliecosmetics by @KylieJenner perhaps?!" she captioned the pic.

The "Kourtney" lip gloss tube definitely seems like a major hint that the oldest and youngest members of the Kardashian-Jenner family are teaming up on yet another of Kylie's makeup collections. But since the famous family are notoriously good at keeping secrets, it could be a while before we see the new collab. For reference, Kylie and Khloé's multi-part Koko collection consists of a few gorgeous pink lip kits packaged in shiny gold tubes and a rosy cheek palette, while Kylie and Kim's KKW by Kylie Cosmetics collection comprised four all-purpose nude lip kits. No matter what products it includes and what shades they come in, Kylie and Kourtney's collab is sure to sell out in minutes.

Related: Khloé Kardashian and Kylie Jenner May Not Confirm Their Pregnancies Until 2018