Kris Jenner is speaking out about her late ex-husband, Robert Kardashian, and the reason why she cheated on him.

Jenner previously admitted to cheating on her first marriage. In the most recent episode of "The Kardashians," she explains why she made that decision.

PHOTO | COURTESY Kris Jenner and Rob Kardashian

Jenner admitted to Khloé Kardashian that she was "really young and dumb" at the time and didn't fully comprehend the ramifications of cheating.

"But what was my dad not doing that made you want to look elsewhere?" Khloé put pressure on her.

"He was such a great husband and such a great dad, and I think that I fell into a situation where I thought that the grass was greener somewhere else," Jenner said.

PHOTO | COURTESY  Kris Jenner and Rob Kardashian

Her affair was her "biggest regret" in life, she said, but "everything happens for a reason."

Jenner divorced Robert Kardashian in 1991. Caitlyn Jenner, with whom she has two daughters, Kendall and Kylie, eventually married her. In 2014, they divorced.