Rob Kardashian's weight gain strugges have been pretty documented but that didn't stop him from launching a new Arthur George loungewear line. Meanwhile, Kim Kardashian and Khloe Kardashian made sure to show their support for their brother.

Khloe Kardashian posted a photo of a model wearing an adult onesie along with the caption: "Sooo proud of my brother @robkardashian!! His new @arthurgeorge87 loungewear line will be in select Macy's stores soon! For a store list and more info go to AGloungewear.com."

Kim Kardashian also made sure that her 26 million Twitter followers know where her support lies: "My brother @robkardashian's @arthurgeorge loungewear line is now in select Macy's stores! Go to AGloungewear.com for store list!"

Meanwhile, momager Kris Jenner has been posting all week about the new Arthur George line along with the hashtag #proudmama.

"But the 27-year-old entrepreneur doesn't seem as excited about the line judging by his silence on his various online profiles," noted  MailOnline.

The reality star cum Kardashian matriarch was previously reported to be at odds with Rob Kardashian over his weight gain. Their spat came to a point when the 27-year-old reportedly had to fly back home from France and skip her wedding to Kanye West.

After coming home, Rob Kardashian allegedly sought out trainer Gunnar Peterson so he can drop off the excess pounds.

In an interview with People, Peterson said: "I think Rob knows exactly what to do. He's worked out [before] and he's focused. We're doing intervals with strength movements: squats, the sled, swings and push presses. It's about getting his heart rate up and keeping it up."

Kris Jenner also earlier admitted that Rob Kardashian is struggling with the weight gain, saying in one of the episodes of "Keeping Up with the Kardashians" that it's very difficult for her as a mother to watch her son wallow in depression and to be helpless in the face of it.