While Rob Kardashian continues to work on losing weight, an insider is speaking out on whether his sister and biggest supporter Khloé Kardashian blames her estranged husband for Rob's reported issue with drugs and alcohol.

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The source close to the Kardashian clan told Hollywood Life Wednesday, "That hasn't crossed her mind. She doesn't even want to open that idea up in her head because it will lead to her mental destruction. If that were the case, she'd strangle Lamar. It would push her over the edge, entirely. She would hope that Lamar would have been a beacon of support for Rob since he's already had problems.

She doesn't want to relive that ugly period of her life that she had with Lamar, when he was going missing for days on end."

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The insider went on to say that Khloé's main priority is to find out where Rob went wrong so she can help him.

One of the rumored ways she tried to help her younger brother was by banning him from the club aspect of her 30th birthday celebrations in Las Vegas this past weekend.

A separate source said, "Rob will be joining in on the festivities for Khloé's birthday, but the family wants him to not join in the club portion of things due to all the temptations it will bring with alcohol. Khloé wants him there for her birthday, but he will be a part of all the private stuff Khloé will do and not the paycheck portion of the night."

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