"My best friend, my heart, my brother," wrote Kylie
Credit: Courtesy Kylie Jenner

As Rob Kardashian continues to struggle in his personal life, half-sister Kylie Jenner is making it clear that she’ll always be there for him.

“My best friend, my heart, my brother,” Kylie, 17, captioned an Instagram photo of Rob squinting in the sunshine prior to his 100-lb. weight gain.

An infrequent Instagram user compared to his youngest sister, Rob recently made headlines when he posted a snap comparing Kim to "the bitch from Gone Girl", while later referring to his honorary brother-in-law, Scott Disick, as a “legend.”

On a recent episode of Keeping Up with the Kardashians, Rob, 28, was vehemently opposed to receiving any outside counsel for his personal issues, to the point where sister Kim insisted that the family start doling out tough love, calling their constant allowances for Rob “pathetic,” adding, “We’re not gonna cater to him anymore, but it has to be all of us.”

“I cry myself to sleep literally every night worrying about [Rob],” said Kris. “It’s breaking my heart.”

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