There's never been a doubt in anyone's mind that Rob Kardashian is definitely team Lamar Odom. And that's why there is a new rumor that suggests the former reality star is feuding with his sister Khloe Kardashian and her boyfriend, James Harden, as Rob is livid that no one is giving Lamar the attention that he needs while he recovers from his drug overdose at the hospital.

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According to Celebrity Dirty Laundry on Wednesday, Rob was close to burying the hatchet in his long-standing feud with his family members, but that all quickly changed after Lamar was found unconscious at a Nevada brothel nearly two months ago.

Sources say that Rob is upset that his sisters have been "faking" their concern for the former NBA star and that he was the only person to step up to the plate to actually volunteer to donate one of his own kidneys to Lamar.

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A source close to the Kardashian family dished, "Rob blames his sister for Lamar's overdose, he says things never would have gotten this bad if Khloe hadn't toyed with Lamar's feelings. And, Rob was disgusted with Khloe when she stepped out with James Harden--while her husband was lying in a hospital bed."

What's more, Rob is none too happy with his mother Kris Jenner and his sister Kim, who have supposedly been trying to cash in on Lamar's hospitalization. A tipster says that he was livid with his family for showing up at his hospital near Las Vegas with a camera crew. As a result, he skipped out on Thanksgiving dinner at Khloe's house last week.

Stay tuned with Enstars for all the latest updates on Lamar Odom right here.