While the Kardashian/Jenner family was in Florence celebrating Kim Kardashian and Kanye West's wedding, Rob Kardashian was back in Los Angeles looking sad and somber. Photographers caught Rob leaving LAX airport on Saturday, May 24, a few hours before his sister exchanged vows.

A source told TMZ that Rob left Paris (where pre-wedding festivities were held) in tears. Reportedly there was some type of "major family drama" the night before the ceremony that caused Rob to bail.

According to X 17 and Hollywood Life, Rob got into a nasty fight with Kim because she was reportedly bashing his weight gain behind his back. The lone male Kardashian was all set to attend the Florence ceremony but left because he reportedly felt like he didn't "fit in," X 17 reports.

A source told Hollywood Life that Kim was upset with Rob because she felt like he wasn't taking his weight loss seriously.

"It got back to Rob and he called her out," the source said, adding that the argument "got heated and everyone decided to take Kim's side."

The sock designer was reportedly "devastated" and decided to leave.

X 17's story mimicked the same thing. A source told the website that "Kim was [upset] that Rob hadn't made an effort to drop any weight over the past few months."

"Rob basically thinks Kim cares about him only for his appearance and he said he'd 'make life easier' for her and just leave," the source added. "Rob booked his flight for Saturday morning and skipped the lunch at Valentino's. He just doesn't seem to feel comfortable or happy around his family at all. They're all wrapped up in the same pretty world and he just doesn't fit in."