Kylie Jenner threatens legal action against Australian business over 'Rise and Shine' t-shirt

Kylie Jenner is very serious about protecting her future billions.

The Kylie Cosmetics makeup mogul, who is the youngest billionaire in the world at age 22, has threatened legal action against an Australian business selling t-shirts that read "Rise and Shine," along with an illustration of the sun and a palm tree. 

The apparent problem? Two weeks ago, Jenner went viral (again!) when she posted a YouTube video of herself singing the phrase "Rise and Shine" to her 21-month-old daughter Stormi Webster.

Jenner is now trying to trademark the slogan "Rise and Shine" and sent a cease-and-desist letter to a Gold Coast woman and mother who owns the brand, called Cased Clothing.

The woman, who declined to be identified, told The Gold Coast Bulletin that she was caught off guard to receive the letter, given that she has sold hundreds of the t-shirts over the past year. Of Jenner, the woman said, "The design wasn't about her, it was just a shirt with a different holiday feel." 

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"We still have a few left but don't plan on selling them now," the woman said, adding that she only has about "eight or so" left.

Cased Clothing has been in operation since 2017 and is linked to her family's enthusiasm for motorsports.

Jenner's original video went viral on October 11, and the next day she began selling US$65 hoodies with the words "Rise and Shine," which remain sold out on her website.

The Keeping Up with the Kardashians star is the sole owner of Kylie Cosmetics, which Forbes valued at an astounding $1.9 billion this year.