It looks like Kris Jenner needs daughter Kim Kardashian’s help! In late September, Rob Kardashian, 30, and Kylie Jenner, 20, filed a lawsuit against his ex-fiancée, Blac Chyna, 29, alleging assault, battery, and vandalism. Now, the momager wants Kim to join the lawsuit as a plaintiff, says a source.

“Lawyers have told Kris that they will get a much bigger settlement if Kim — the most popular Kardashian — is a plaintiff. A jury would definitely side with Kim!” a source tells In Touch. The reality star wants to help her siblings, but she’s hesitant. Kim, 36, “has pointed out that she [doesn’t] have a legal claim against Chyna." But Kris, 61, is claiming that Chyna leaked “negative stories about Kim to the media. Even though Chyna was under a strict NDA, she was blabbing.”

Even if Kim does agree to come on board, it likely won’t fly with her hubby, Kanye West, 40. Before Rob and Kylie filed their suit, Kim considered becoming a plaintiff, but Kanye convinced her to back out right before papers were filed. “With a new baby arriving [via surrogate], Kanye wants Kim to focus all of her attention on their family,” says the source, adding that Kris can try to change Kim’s mind all she wants, but as of right now, “It likely won’t be happening.”

As In Touch previously revealed, Chyna is more than ready to fight back against these allegations and expose the family's dirtiest secrets. “She is planning to reveal everything she knows about the Kardashians,” a source says. “Kris Jenner and Kim Kardashian are terrified.”

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