Kylie Jenner founded Kylie Cosmetics in 2015 at age 17 with a $29 lip kit and leveraged her massive Instagram following to generate $420 million in sales in the first 18 months — reaching a reported $800 million valuation before selling a 51% stake to Coty Inc. for $600 million in 2019. Born in Los Angeles in 1997, Jenner built her brand entirely through social media, bypassing traditional retail and advertising channels. Kylie Cosmetics became the defining case study of social media-native brand building — demonstrating that a sufficiently engaged personal audience could launch a consumer products company faster than any traditional marketing budget could.

Reference:

Kylie Jenner on Wikipedia

https://en.wikipedia.org/wiki/Kylie_Jenner