Earlier this week Rob Kardashian posted sister Kylie Jenner's phone number on Twitter after finding out she and his other sisters planned a baby shower that did not include his baby mama Blac Chyna [click here if you missed that].
A source close to the family explains what REALLY happened...
From Ace Showbiz
"Here's what happened: Kim threw the shower. Kylie [was] the one that Rob called and told he wouldn't go to the shower, because she mentioned it was being filmed," the source explains.
"He [then] got really upset and told her he wasn't going, but that Chyna still wanted to go. Chyna was all dressed up and ready to go, [but] Kylie then told him that Chyna wasn't invited if he wasn't going to be there."
"She said it was his shower and Chyna could come if they were together - but if he was going to screw them by not going, then Chyna couldn't come," the source continues.
"That's when Rob exploded. It caused a huge fight between Rob and Chyna too, so that's when Rob went off on Kylie on Twitter."