Kris Jenner confessed to the affair in her autobiography. She was married to Robert Kardashian, Kim and Kourtney's dad, when she strayed.
The two ultimately divorced and in 1991, Kris married Bruce Jenner.
In their lunch time chat, Kourtney revealed that she was angry that her mom had to bring up her infidelity in her book.
Kim told her to talk it through with their mother because "you have this resentment towards mom."
Kourtney doesn't disagree, calling her mom's actions "selfish."
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