Rob Kardashian attends the Sky Beach Club on May 28, 2016 in Las Vegas, Nevada. Credit: Gabe Ginsberg/Getty Images

Time out, young man! Rob Kardashian and fiancée Blac Chyna are expecting their first child together, but the reality personality is already showing he can be a good daddy.

The pregnant video vixen, 28, shared an adorable video on Instagram on Saturday, August 20, of her husband-to-be chiding her son, 3-year-old King Cairo, whom she shares with ex-fiancé Tyga.

“I’ve had this video for a min and it cracks me up!” Chyna wrote of the clip, sprinkling several laugh-cry emojis in her caption. “My favorite part is when Rob jumps out … look at his face … But overall I”m so happy and blessed to have Robert here willing to teach King right from wrong.”

In the video, the little boy is playing with a mobile device as it records him peeking under the bed before he lets out a very unexpected “Awww, s—t!”

A video posted by Blac Chyna (@blacchyna) on

“What?!” the Arthur George sock designer, 29, can be heard exclaiming. “What did you say?!”

King Cairo drops the S-bomb a few more times before a disheveled-looking Rob — who seems to be in bed — appears in the video and scolds the little boy.

“No, you can’t say that. Don’t say that. That’s a bad word,” he tells Chyna’s son. “Your mommy’s gonna get really mad at you.”

When the tyke drops the curse word one more time, the reality personality says a bit more forcefully, “No! You can’t say that!”

As Us Weekly exclusively reported in July, Kardashian and Chyna are expecting a baby girl, who is due in October. “Rob couldn’t be happier,” a source told Us at the time.

While the engaged pair await their daughter’s arrival, the Keeping Up With the Kardashians star is doing what he can to make sure his expectant love is properly pampered. In their first Facebook Live chat on Wednesday, August 17, promoting their upcoming reality show, Rob & Chyna, he revealed that he spent $13,000 in one month on food delivery to satisfy his love’s pregnancy cravings.

The duo also revealed that they plan to have several more children. “Rob wants me to have, what, four more?” Chyna told fans during the chat.

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