In handwritten diaries by the late Robert Kardashian, father of at least Kim and Kourtney Kardashian, he wrote that his ex wife Kris Jenner would physically abuse and threaten her children, which in hindsight really does seem like something Kris Jenner would do.
In the journal entries, dated throughout 1989 and 1990, Robert paints a heartbreaking childhood portrait of Kim, Kourtney and Khloé and a damning picture of mom Kris Jenner. "Kris was kicking and beating her and said she was going to kill [Kim]!" Robert claimed in his diary on Aug. 24, 1989. "Kim was hysterical."
So far there's no reason to doubt the authenticity of the diaries and since these were never intended to go public there's no rational explanation for why he would lie. Another interesting note is that if you check Kris Jenners diary from August 24, 1989, it says, "had to teach Kim a lesson today. Bet she won't even think about dating a black guy again."
(source = intouch)