The Kardashians Plan to Expose Blac Chyna in 2017 (EXCLUSIVE)

The Kardashian sisters have had enough of their future sister-in-law Blac Chyna — as a source exclusively tells In Touch they have reason to believe that she’s emotionally abusive to Rob Kardashian.

“They believe his fiancée, Blac Chyna, has been psychologically abusive to Rob,” a source tells In Touch, adding that they think Chy is to blame for his dangerous habits when it comes to drugs and eating.

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“At first they thought she was a positive influence, but they now believe she is killing him. So after Rob’s emergency trip to the hospital, his family hatched a plan to get rid of Chyna once and for all.”

An insider tells In Touch that they’ve heard “so many bad things” about Chyna, including claims that she cheated on their brother. Momager Kris Jenner has even turned to a private investigator to get to the bottom of the drama.

“They family is writing everything down and will present it to him,” the insider explains. “They will sit him down for an intervention and place an envelope containing all the proof of what she has done on the table in front of him. They want to have a psychologist on hand so they can discuss how Chyna abuses him.”

Chyna’s history of abuse has been well-documented — she famously called him “fat, lazy, and insecure” in private text messages that were exposed after her phone was hacked. She subsequently left Rob — taking her two children with her — and abandoned him and their new house just before the holidays.