Are Kendall and Kylie feuding?

If you have a sister, you probably butt heads with her from time to time, and according to sources, Kendall and Kylie Jenner are going through one of those rough patches! The topic they're rumored to be fighting about? Their looks! "Kendall was always considered the pretty one while Kylie was totally overlooked," a source says. "Kylie's been seething with resentment for a long time." Apparently, Kendall has a lot to say about Kylie's alleged plastic surgery, too! "Kendall thinks Kylie looks ridiculous, and she doesn't hold back from telling her so." We'll wait for more evidence before we believe this one!