"What do you want?" Disick, 33, asks in the preview.
"A boy. You gotta carry on that name," Kardashian replies.
"I'm definitely hoping for a boy because I want to have the same relationship that I had with my father with my son," he adds in a confessional. "So that's what I'm praying for."
Kardashian's late father, Robert Kardashian, died at the age of 59 from throat cancer in September 2003. The lawyer, who famously defended his friend O.J. Simpson during the athlete's 1995 murder trial, was married to Kris Jenner from 1978 to 1991.
Last week, Kardashian posted a throwback photo of his dad on Instagram and said that he "can't wait" for fatherhood.
Kardashian will have to wait for his dream to have a son. As Us Weekly exclusively revealed in July, he and Chyna, 28, are expecting a baby girl.
Back in June, the model opened up about what kind of father she thinks Kardashian will be. "Overprotective! For sure. Loving, caring," she told Entertainment Tonight at the time. "Rob is just a big bundle of joy."
Rob & Chyna premieres on E! Sunday, September 11, at 9 p.m. ET.
Watch the sneak peek in the video above!
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