Back in December, Rob launched a war of words against Ora on the social-networking site, accusing the Radioactive singer of cheating on him with "nearly 20 dudes", while also claiming he got her pregnant.
In a new clip from their reality TV show, sister Kourtney Kardashian is seen warning her younger sibling to stop lashing out at Rita on Twitter, adding: "She’s the one that’s in the wrong, but she’ll probably try to make it like you’re in the wrong."
Kimmy agreed: "Don’t post anything else, everyone has problems."
Rob then hit out at Kim in a series of texts, with the socialite telling the cameras that one of his messages said: "I hope your sex tape haunts you for the rest of your life, and I’m going to publicly bash you and Kanye."
He later apologised to Kimmy, telling her: "Obviously the things I said to you in the text message, I was just being mean."
Kim - who is expecting her first child with Kanye West - then added: "I don’t know who he is hanging out with, but I feel like it’s not him. He has so much going on and he is depressed."
Rob later explained why he decided to attack Ora over Twitter, stating on the E! series: "I posted what I posted to keep myself from taking her back.
"Every time she messed up, I took her back for over a year now. I just had to do that to make her hate me."
After his initial outburst, Rita told Glamour magazine: "I'm not going out with Rob. We were close for a while, but it didn't work because I was never there."
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