Khloé Kardashian is concerned about her brother Rob's recent wild partying.
The 30-year-old star is worried the 27-year-old sock designer will go down the same path as her ex-husband Lamar Odom - whom she filed for divorce from in December amid rumours he was addicted to cocaine - but she doesn't know how she can help him.
A source told the HollywoodLife.com: "Khloé can't think right now, she's just in disbelief right now that her little brother is going through these issues.
"She realised he's been troubled for a long time now but was in the dark that it's reached this level.
"She feels low because she's been through this before with her ex and it's all too familiar and another earthquake that's rocked her core."
The brunette beauty has tried to reach out to Rob - who failed to attend his other sister Kim's wedding to Kanye West last month following a disagreement - but he has reportedly shunned the whole family.
The source explained: "She would drop her entire life for him and Rob knows that. And that's what killing her the most. He has everything, every resource of Khloé's and the family's at his disposal but he's choosing not to use them. It's a slap in the face."
Rob has plunged into severe depression recently after gaining more than 60lbs since being dumped by British popstar Rita Ora in late 2012.
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