The 18-year-old appeared to post a meme of the devil to Instagram on Monday. In a screengrab by The Shade Room of the since-deleted post, Jenner wrote “this is @robkardashian lol” under a Tweet first shared by user Nina la Cochina.
The original post featured a hand-drawn image of the devil with the text “my 7 year old little brother just drew this what does this mean?” and the response “It means He’s Not Your Brother Anymore Bitch Get Out The House.”
A source previously told PEOPLE that “Kylie is livid” about her older brother’s rumored relationship with Blac Chyna, whose birth name is Angela Renée White.
“She feels super betrayed and can’t understand why someone in her own family would stab her in the back like that,” the source said.
Blac Chyna was once engaged to Tyga and the pair have a 3-year-old son, King Cairo. She was once friends with Jenner’s sister Kim Kardashian West and is now close with Kanye West‘s ex Amber Rose, who feuded with Kylie’s older sister Khloé Kardashian last year over Kylie’s relationship with Tyga.
While 28-year-old Rob has stayed mostly out of the spotlight over the past year, it appears he’s spending time with Blac Chyna, who shared a close-up, black-and-white photo of herself with a heavily tattooed arm that looks like Rob’s.
Khloé also added her voice to the drama on Monday, writing on Twitter that a previous note about a family member bailing on her talk show could “go towards a few people.”
She initially posted a pointed, cryptic tweet: “You can do anything. But never go against the family.”