Kan’t Keep Up! Kim ‘Fuming’ Over Sister Kylie’s Coveted 'Forbes' Cover

Kylie Jenner was named as the 27th richest woman in the world today by Forbes Magazine after earning more than $900 million over the past three years — and sources tell RadarOnline.com exclusively Kim Kardashian is "fuming" over it!

As the 20-year-old sets her sights on being the first woman in history to hit the $1 billion mark by the time she is 21 years old, insiders say her bitter sister has a different goal in mind – taking her down!

“Kim may have congratulated Kylie on social media for the cover, but inside she is fuming over this,” an informant told RadarOnline.com exclusively.

According to the source, Kardashian, 38, who launched KKW Cosmetics after seeing how successful her sister had done with, “is doing everything that she can right now to expand KKW to include every type of makeup imaginable. She just can’t let Kylie win.”

“Kim cannot believe that Kylie did in three years what she has not done in her entire life so far. She even told her family that she created Kylie and that she would be nothing without her,” the insider added.

As RadarOnline.com previously reported, the feuding between Kardashian and Jenner — which really started five years ago over Jenner’s copycat fashion choices — has escalated after Kardashian launched KKW, which has not earned her nearly as much money as her youngest sibling.

Forbes even took a dig at Kardashian in the feature, which listed the wife of Kanye West as the 54th richest with $350 million — falling just behind nemesis Beyonce, who came in at #53 with $355 million.

The article stated: “What her half-sister Kim Kardashian West did for booty, Jenner has done for full lips. Like Kardashian West, she has leveraged her assets to gain both fame and money. But while her sister is best-known for the former, Jenner has proved adept at the latter. In historic fashion."

Meanwhile, Jenner's baby daddy Travis Scott is reacting completely different to the news his girlfriend is close to becoming a billionaire. “There’s no doubt in Travis’ mind that he wants to marry Kylie, especially now that he knows she’s a legit billionaire," a source claimed. "He feels he hit the jackpot and now isn’t worried if one day his rap career fizzles out.”