Rob Kardashian's weight gain reportedly ended with him in fat camp as momager Kris Jenner insisted on bringing her only son to extreme weight loss program.

On Monday, Kris Jenner was snapped about to board a private plane from Van Nuys airport but Rob Kardashian was nowhere in sight. MailOnline said that the sock mogul was already on the plane when the momager was photographed,

Kris Jenner supposedly got what she wanted from Rob Kardashian's weight gain by personally accompanying him to fat came, the website X17 reportedly talked to a source who confirmed the report.

A representative for Kris Jenner did not release any statement regarding the report.

Last week, the "Keeping Up with the Kardashian" star spent his 27^th birthday and Kim Kardashian unwittingly drew attention to Rob Kardashian's weight gain by posting an old photo of him much slimmer.

Kim Kardashian captioned the photo with: "Happy Birthday to my baby bro @robkardashian. I love you soooo much!!!!"

The photo was taken two years ago while they attended 1OAK in Las Vegas and the youngest Kardashian was still thin, which the website said only put a spotlight on Rob Kardashian's weight gain.

Rob Karashian also posted a selfie photo on his own Instagram account showing him wearing a navy blue bandana covering half his face.

The photo was simply captioned: "Happy birthday to me."

In the recent episode of "Keeping Up With the Kardashian," Kris Jenner told Rob Kardashian to watch his weight or he might die.

"This is life-threatening at this point. You can only sustain this level of being unhealthy for so long," she said of Rob Kardashian weight gain.

But Rob Kardashian is also aware of his weight gain. "I've never felt so down depressed in my life. I'm trying to be in the fashion industry and I'm not going to be taken seriously when I'm fifty pounds overweight. It's embarrassing to the family," he said, according to UK's Mirror.