The 29-year-old reality star even made a NSFW joke at his mother Kris Jenner's expense.
Rob Kardashian was anything but camera shy while out and about with his older sister, Kourtney Kardashian, on Monday.
A recent report claimed the 29-year-old reality star was skipping out on filming his six-episode docuseries, Rob & Chyna, with pregnant fiancee Blac Chyna, but a source told ET that he is still shooting the show, though he does still have the occasional "mood swings."
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A little brother-sister bonding time with Kourtney seemed to pull Rob out of his "rut," because he was happily making jokes while driving his sibling around town. "There is something so wrong with my brother, I just want you guys to know that," Kourtney quipped in a Snapchat video.
As the snap continued, Kris Jenner is heard on the phone with her son and he makes a very NSFW joke at her expense. "Hey mom, why don't you shove your d**k in my mouth?" Rob exclaimed as he and Kourtney start laughing.
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While he didn't appear to have any qualms being a part of Kourtney's Snapchat story, Rob's social media presence has been sparse since deleting all his Instagram photos last month. "He goes through his dark periods," the source close to Rob told ET. "He gets depressed and doesn't want to really do anything, doesn't leave the house. It got better for a bit when he first started dating Chyna, but he's in a rut now. He'll snap out of it."
Rob and Chyna have been dodging split rumors ever since he wiped his social media account, but put all that speculation to rest when they both shared videos of one another on Snapchat last week.
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"She gave him confidence, more power to her," Kim Kardashian West said of Chyna's relationship with her brother on a recent episode of Keeping Up With the Kardashians. "Even if there's been some drama ... If this is what it takes, then I don't care who he's dating. I'm so happy that he's just feeling better about himself."
