Every party has a pooper. Kim, Kourtney and Khloé Kardashian are stunned when they find out that their brother Rob doesn’t want to attend the baby shower they’d been planning for him and his fiancée, Blac Chyna, for the next day, as seen in a preview for Keeping Up With the Kardashians' season 12 finale on Sunday, November 20.

"Rob and Chyna are fighting again," Kim, 36, tells her sisters as they gather around the table to discuss what to do. “He said that he doesn’t want to celebrate a shower because this pregnancy has been really bad for him and really awful for him.”

"What’s the fighting about? Like, intense?" Khloé, 32, asks Kim.

“She texts him crazy things. He texts her crazy things all night long,” Kim reveals. “He just doesn’t want to go to the shower.”

Khloé is quick to dismiss Rob’s drama and tell it like it is: “You guys, our brother is coming to the shower,” she says. “That’s crazy.”

As the sisters debate what to do about the party, they all agree on one thing: Their mother, Kris Jenner, will be crushed if the Arthur George sock designer doesn’t show. 

“We just really want to do this for Rob, especially my mom,” Kourtney, 37, explains to the camera. “She’s so excited to give him presents and just really celebrate him.”

“I feel like we should try to get him to come for Mom,” Khloé decides. “If it’s for nobody else, it should be for her. She does so much for him.”

A source previously told Us Weekly that both Rob, 29, and Chyna, 28, opted to skip the September 22 shower that his family had been planning because the couple weren't pleased that the event would be filmed for KUWTK. Rob and Chyna welcomed daughter Dream on November 10.

Watch the dramatic clip above, and tune in to the Keeping Up With the Kardashians season 12 finale on E! Sunday, November 20, at 9 p.m. ET. 

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