Rob Kardashian is mad at his sister Kim Kardashian for making negative comments about his weight.

The Kardashian brother was furious after hearing that Kim K told Rolling Stone that he would actually be "skinny" if he was using meth.

"Rob and Kim had been cool again and were getting along," an insider tells Us Weekly. "Now he's furious at her again for her comments to Rolling Stone. He was been b**ching her out on her phone."

Rob has had issues with his family in the past, between battles with depression and failed business attempts. He has kept a low profile for the past two years and has not appeared on the famous family reality show "Keeping Up With the Kardashians."

"It's not that mysterious, what's happening with Rob," Kim told Rolling Stone when she was asked about her troubled brother. "He has gained weight. He feels uncomfortable being on the show, and that's OK."

The 34-year-old said she believed her 28-year-old brother was smoking marijuana with friends. She then joked that he would "be skinny" if he was doing meth when Rolling Stone asked her if he was dealing with "meth and hookers at the Ritz."

Meanwhile, Kim is pregnant with her second child after trying for so long and this time it's a boy.

She talked about her relationship with her rapper husband Kanye West stating that she appreciates what he does for her. "The makeover Kanye has given me is amazing," she gushed.

The reality star also said that she first saw Caitlyn Jenner before her transition dressed in women's clothes when she was just 22 years old.

"I was shaking," Kim said. "I didn't know if I'd just found out his deepest, darkest secret, and he was going to come after me."

Caitlyn Jenner is now open to the world about her gender identity.

Rob was last spotted at an In-N-Out burger last month.