If you’ve been wondering why Caitlyn Jenner was a no-show at her daughter Kylie Jenner’s high school graduation, you’re not alone. Caitlyn wants to know why, too.

In a new clip from an upcoming episode of I Am Cait, Caitlyn confronts her ex-wife, Kris Jenner, about failing to receive an invitation to the celebration.

Kris starts off the conversation, saying she wants to clear the air with Caitlyn. She said, “One of the reasons I wanted to talk to you was because I don’t want your feelings to be hurt like the other day when I heard that you weren’t happy about not being included in Kylie’s graduation.”

Caitlyn fires back, saying it was unfair that she wasn't included, especially considering that, you know, Kylie's her kid: “It wasn’t me making that decision. It was you making that decision. I was so disappointed in everybody. For 15 years of my life I carpooled kids everyday. Some days I would spend three or four hours in the car. [It's] a slap in the face when you don’t even get invited to their graduation.”

Then Kris compares this very specific situation to her relationship with Caitlyn and how she felt blindsided by her Vanity Fair debut. Caitlyn shuts this down immediately, saying, "It’s not tit for tat. Vanity Fair was months ago. We’re talking about what happened a few days ago."

Kris attempts to explain further, saying, “Listen, usually people that get a divorce don’t do everything together. It wasn’t malicious, I didn’t intend to hurt anybody’s feelings, but my feelings still weren’t healed."

You can check out the clip above, and catch the upcoming episode of I Am Cait when it airs on September 13 on E! at 8 EST.

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