Rob Kardashian rarely posts to Instagram, so when he shared a bloody picture of “Gone Girl” character Amy Dunne and compared her to his sister Kim, thousands of his fans were shocked. Now, an insider has told People magazine the only Kardashian brother, who has struggled with his weight, is in a bad place.

"He's been depressed and just a bit off in general," the insider told the magazine. "But he has always been this way. He just can't lose the weight and he doesn't try -- he just sits around." 

It's believed that Rob's weight gain is the root of his unhappiness. In 2013, Rob admitted to gaining more than 40 pounds. "It's crazy how this whole year, my whole relationship was only negative. All I did was gain f---ing 40 pounds and lose so much money," he told the cameras on “Kourtney and Kim Take Miami.” "I'm so insecure. I weigh like 215 pounds. I hate pictures. I hate everything."

Rob Kardashian Rob Kardashian potentially started a family feud Sunday when he posted a graphic picture and labeled Kim a b----. Photo: Instagram/Rob Kardashian

While it seems like a family feud could be brewing, a different source said there might not to be anything to worry about -- Rob has a quirky sense of humor, and the whole thing could be a joke. "He has a funny sense of humor and posts weird things and then deletes them," a Kardashian source told People. "It's just him." 

Except, this time Rob hasn’t deleted the post. None of the Kardashian-Jenner siblings commented on the aggressive post, and instead plugged the newest episode of “Keeping Up with the Kardashians” where Rob isn’t mentioned.

Even sister Khloe, who considers herself Rob’s “No. 1 supporter,” said her brother isn’t in the best place. “I just feel, especially over the last year, Rob has become very introverted and has a kind of social anxiety,” she told MSN’s Wonderwall. “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.”

Since the graphic post about Kim, where he wrote, “This is my sister Kim, the b---- from ‘Gone Girl,’” Rob has stayed off Instagram and Twitter.

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