The momager and her daughter, Khloé Kardashian, were talking about Tristan Thompson when Khloé asked her mother about cheating on her father, Robert Kardashian Sr. with animator Todd Waterman in 1989.
"What was your mindset when you cheated?" Khloé asked. "When you did that with my dad, and you had four kids and you had a family? Yes, I know you were really young."
Kris said her only explanation was "being really young and dumb,” which “is something that plays into it because you don’t really understand the consequences of your actions."
"But what was my dad not doing that made you want to look elsewhere?" Khloé responded.
Kris confessed, "I don't know because 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, and I made a huge mistake. That’s my life’s biggest regret."
Kris is still thankful for how everything turned out, telling Khloé, "I'm not proud of way I behaved during that time, but you know what? Everything happens for a reason. I really do live my life by thinking God has a plan, and without that whole thing happening, there never would’ve been Kendall and Kylie [Jenner]."
According to People, Kris shared more in her confessional, saying that she hopes Khloé won’t cut off Thompson, with whom she shares 5-year-old daughter True and 13-month-old son Tatum.
"When I got divorced, Robert and I became best friends. We talked on [the] phone all day long, helped each other through things all the time, and I did have regrets," Kris said. "I thought, 'Wow, what I was thinking? 'So I want Khloé to be really careful when she makes these decisions and she has to let somebody go."
Kris and Robert Sr. were married in 1978 and had four children together: Kourtney, Kim, Khloé, and Robert Jr. The couple later divorced in 1991, but not before Kris met Caitlyn Jenner—then Bruce Jenner—in 1990.
The pair said their I do’s a month after Kris finalized her divorce, in April 1991, and later had two daughters together, Kendall and Kylie. In 2003, Robert Sr. was diagnosed with esophageal cancer and died less than two months later at 59 years old. Kris and Caitlyn later divorced in 2014, and Caitlyn came out as trans in 2015.