Rob Kardashian surprised millions of Kardashian fans Sunday when he posted a picture of bloody “Gone Girl” killer Amy and said, “This is my sister Kim.” But before he unfollowed his entire family on Instagram, sister Khloe told MSN’s Wonderwall Saturday Rob suffers from a form of social anxiety.

The youngest Kardashian sister was hosting a party at 1 OAK nightclub in Las Vegas and dished on her brother, who has strayed from the public eye for years after a massive weight gain. “I just feel, especially over the last year, Rob has become very introverted and has a kind of social anxiety,” she said. “He’s definitely not at his happiest place that he once was, and I know he can get to that happy place and he will.”

In a promo for Season 10 of “Keeping Up with the Kardashians,” the family show on which Rob rarely appears, momager Kris Jenner contemplates doing an intervention and Khloe can be seen pleading on the phone with him to get help. She has always claimed to be the closest with him among the siblings and calls herself his “No.1 supporter."

“We all kind of get to a place where you don’t know where to go in life or whatever, so I think it’s important for him to know that he always has people to lean on and it’s not unnatural for people to not know even where to begin. It’s a growing process,” Khloe told Wonderwall.

Sightings of Rob in public are rare. He ditched Kim and Kanye West’s Italian wedding nuptials because of his weight and hasn’t been photographed since. The Arthur George sock designer isn’t discussed much on “KUWTK,” except for his struggle with weight loss and refusal to attend public events.

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