"We don't care what you're doing, meaning we don't care if you want to transition, we want to support you and be there for you. But we don't think that that entails you speaking negatively about my mom," the 31-year-old explains in a tense conversation with Caitlyn, 65.
"In our opinion, you don't need to even mention our mom. Let's focus on the actual cause here, and let's not drag my mom through the mud," she adds in the clip, released exclusively on E! News. "I would think you would come from a place more of compassion, especially when you have two young daughters who are greatly affected by it."
All seems to be well between the exes now: Caitlyn sat with Kris and her boyfriend Corey Gamble at their daughter Kylie Jenner's 18th birthday party on Sunday, gamely posing for a selfie along with Kim Kardashian West and Kourtney Kardashian.
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I Am Cait airs Sunday at 8 p.m. ET on E!