Rob Kardashian: Did He Know About Lamar Odom Drug Use? >>Hollywood

Kim Kardashian may have been in the dark over her brother-in-law's tumble off the wagon, but a new report makes it clear:

Rob Kardashian has been seeing the tragic light for some time now.

Rob has "known about Lamar's drug addiction for over a year," an insider tells Radar Online. "How could he not as he has lived under the same roof with Lamar and Khloe?"

Kardashian is especially close to Odom, who anonymous friends allege has fallen into serious cocaine use. Khloe is reportedly doing all she can to get her husband the help he needs.

This report, however, cites Ambien and OxyContin as the vices of which Kardashian was aware.

"Rob isn't a party animal like Lamar, and drugs just aren't his scene," the source adds. "The two used to be very close, but have drifted apart because Lamar has been abusing Oxy and cheating on Khloe."

Ah yes, then there's that: the cheating allegations.

Jennifer Richardson and Polina Polonsky have both come out and claimed they carried on affairs with the basketball star, accusations that have seemingly been forgotten about in light of the new drug rumors.

Interestingly, Radar claims Lamar "is really trying to make amends with both Khloe and Rob," but you may be surprised who the harder sell has been so far:

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