Rob Kardashian Gets Support From Khloe Kardashian on Weight Loss Challenge: "I Believe in You"

USMagazine, Friday, February 22, 2013, 9:00am (PST)

Supportive sister! Rob Kardashian is determined to lose 50 pounds and sister Khloe Kardashian will be cheering him on along the way.

"Another fat boy breakfast. Let's go! 5 mile run next. 50 pounds got to go!" Rob, 25, tweeted Thursday, Feb. 21. "I believe in YOU," Khloe, 28, wrote back.

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In the Feb. 17 episode of Kourtney & Kim Take Miami, Rob revealed that he was packing on the pounds during his turbulent year-long relationship with pop star Rita Ora. "It's crazy how this whole year, my whole relationship was only negative. All I did was gain f-cking 40 pounds and lose so much money," he said on the show. "I'm so insecure. I weigh like 215 pounds. I hate pictures. I hate everything."

After gaining an additional 10 pounds after the episode was filmed, Rob has come up with a diet and exercise plan that he's documenting on Twitter.

"This is what fat boy now has to eat for breakfast today," the sock designer tweeted with a photo of his plate. "So much fun! Lol. Cardio time!" In a more positive post, Rob shared a photo of his dinner and wrote, "Goodness I can cook! Swordfish, kale salad, asparagus. Beast mode."

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Rob's sisters have tried to help him lose weight in the past.

On part one of Kim Kardashian's Fairytale Wedding special in October 2011, Khloe and husband Lamar Odom installed an alarm in their kitchen to stop Rob from his midnight snacks. Rob then moved out of Khloe's house and into Kourtney Kardashian and Scott Disick's home, but Kourtney tried to force him to follow her diet.

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Instead, Rob worked on shedding the pounds by competing on Dancing With the Stars in 2011. You probably wouldn't know, but I'm the most insecure and overweight I've ever been," he confessed to Us Weekly at the time. "I'm over 200 pounds, so I want to drop weight and this will be a good start."

This article originally appeared on Usmagazine.com: Rob Kardashian Gets Support From Khloe Kardashian on Weight Loss Challenge: "I Believe in You"