Kylie Jenner is Reportedly 'Livid' With Rob Kardashian for Dating Blac Chyna

Kylie Jenner is not very happy with her brother Rob Kardashian.

According to People, the 18-year-old reality star is really upset he’s dating Blac Chyna, the ex-fiancee of her boyfriend Tyga, with whom he shares a child, King Cairo, 3.

“Kylie is livid,” a source told the mag. “She feels super betrayed and can’t understand why someone in her own family would stab her in the back like that.”

Rob and Blac Chyna first sparked romance rumors when she posted an Instagram photo of them getting cozy, which you can see below.