Los Angeles, California - Are Kylie and Kendall Jenner the next Kar-Jenner siblings to be locked in a rivalry?

The Jenner sisters just showed fans what dreams are made of for Halloween. Yet, an insider told Life & Style that the beauty mogul and the runway star are allegedly feuding.

The tipster tattled that while Kylie and Kendall are leaning on each other amid any recent backlash they've had from fans and the fashion industry, their private fights "have been epic, even worse than anyone has seen on TV."

"It gets ugly, physical even, very down-and-dirty," the source added.

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They explained that Kylie and Kendall are highly competitive with each other, and their feud is "rooted in jealousy" over "who their mom pays more attention to, who's the most popular."

"Kylie loves to hit below the belt with that," the tipster added. "It’s a sore spot for Kendall and makes her feel like the black sheep of the family."

Are the Jenner sisters headed towards a feud as explosive as Kim and Kourtney Kardashian's? Then again, as Kimmy and Kourt explained after the misconceptions over their relationship, maybe sibling rivalries are normal – especially in the Kar-Jenner house.