Kris Jenner and Caitlyn Jenner are reportedly having some co-parenting issues, and Caitlyn doesn’t like the fact that Kris has left her out of a very important family event for their daughters Kendall and Kylie Jenner.

Back in July, Kris Jenner threw a graduation bash for both girls after Kylie fulfilled her requirements for homeschooling. Kendall had finished hers up several months before. The bash was a graduation celebration for both Kylie and Kendall Jenner, but Caitlyn wasn’t invited.

The former couple argued about the omission in a recent I Am Cait clip.

Kris Jenner makes Caitlyn Jenner cry in this emotional #IAmCait clip—watch now: http://t.co/biAuHa33wU pic.twitter.com/IMzY8qAABU

— E! Online (@eonline) September 10, 2015

“It wasn’t me making that decision. It was you making that decision,” Caitlyn Jenner said. “For 15 years of my life, I carpooled kids every day. Some days, I spent three or four hours a day in the car. [It’s] a slap in the face when you don’t even get invited to their graduation.”

“Listen, usually people who get a divorce don’t do everything together. It wasn’t malicious,” Kris Jenner said, right after bringing up Caitlyn’s Vanity Fair cover.

Caitlyn Jenner makes a very valid point. It’s not like Kris Jenner didn’t issue an invitation to Sunday dinner. It was a graduation celebration for the daughters that Caitlyn–as Bruce–played a huge role in raising.

Do you think Kris Jenner was being malicious in omitting Caitlyn from the list of invitees?

Caitlyn Jenner confronts Kris Jenner over why she wasn't invited to Kylie's grad: http://t.co/l32GIaaR03 #IAmCait pic.twitter.com/52Tz5TSyDj

— I Am Cait (@IAmCait) September 10, 2015

Is the Keeping Up With the Kardashians matriarch still struggling with the fact that Caitlyn Jenner was once Bruce Jenner–the man to whom she was married for more than 20 years?