Clearly, Khloé Kardashian doesn’t believe the old saying “once a cheater, always a cheater.” Perhaps she was able to see past her baby daddy Tristan Thompson‘s indiscretions because someone she loves has done the same thing — her mom, Kris Jenner. Despite feeling the sting of a cheating scandal herself, Koko defended her mom’s past affair when her sister Kourtney attacked her for it in a new trailer for Keeping Up with the Kardashians on Sept. 20.

“For some reason you do not give mom the benefit of the doubt, ever. It’s really unfair” said 34-year-old Khloé, bringing up Todd Waterman, a then-23-year-old soccer player who Kris, 62, famously cheated on Robert Kardashian with. She has since described the scandal as “one of my biggest regrets in my life.” However, she thought Kourtney, 39, might relate now that she’s dated a younger man.

“You have your own Todd, right now,” said Kris. “No, I actually don’t,” Kourt clapped back. “I’m actually not married, and I’m not having an affair. You can’t compare one to the other, that’s absolutely not true.” 

Despite recently going through the pain of being cheated on by Tristan, Khloé defended Kris against Kourtney. “I’m just saying, sometimes memories get a little warped by our age. Don’t be so hard on your mom,” she said. Kourtney didn’t seem particulaly receptive, but maybe Koko learning to forgive her mom is what helped her learn to forgive her own boyfriend when he was caught cheating just days before their first child was born.

Khloé learned to understand both sides of a cheating scandal from watching her parents go through it. In 2016 on her show Kocktails with Khloé, she said, “I saw how it destroyed my dad. I saw what it did to my dad, so I don’t want to do that. I also saw the regret of my mom.” Hopefully Tristan was just as apologetic and regretful. You can watch the drama between Kourtney and Kris unfold on Keeping Up with the Kardashians, on Sunday at 9 p.m. on E!