Sibling rivalry is nothing new for the Kardashian-Jenner clan — especially when it comes to Kim Kardashian, 36, and Kylie Jenner, 19!

A source revealed to Hollywood Life what Kylie thinks of her big sis launching her own cosmetics line, called KKW Beauty — and the reaction is not what fans were expecting.

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“Kylie is proud, she feels like she inspired Kim to get into the makeup game. She never imagined there’d be a day when Kim would be following in her footsteps, it just shows how much things have changed,” said the source. “But there’s still competition between them, Kylie does worry that her big sister will come in and take over. She likes that Kim is copying her but wants her to stay in her own lane.”

https://www.instagram.com/p/BVSftcdFeve/

We are sure Kylie will still make a sick profit off of her successful brand called Kylie Cosmetics since her company has been established and she has a loyal following — and KiKi will most likely turn to her sister for advice when it comes to KKW Beauty. However, it would hardly be surprising if Kim was trying to take her sister down, as she allegedly had a lot of opinions about Ky getting her own spin-off series called [Life of Kylie](http://www.eonline.com/shows/lifeofkylie).

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“Kim feels like she put the family on her back and turned each one of them into a household name and that they should be thanking her daily. Instead, she feels like she’s being fazed out by Kylie’s fame and her ability to make money so easily and blames [their “momager”] Kris [Jenner] for making everything so effortless for Kylie. When Kim was coming up, she had to do everything herself. Kylie will never know the real struggle,” an insider previously revealed.

Mrs. Kanye West shared the exciting news with her followers this week and her line will launch on June 21.

Scroll through the gallery to see more times Kim and Kylie were the same person!