Potty mouth!

Rob Kardashian's parenting skills were put to the test in a recent video his fiancée Blac Chyna shared to Instagram. In the vid, Chyna's three-year-old son King Cairo — whose father is her ex Tyga — can be heard saying a cuss word.

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Upon hearing King utter the curse word, Rob says, "What did you say?"

King responds, "I said s–t."

Rob says, "You can't say that. Don't say that. That's a bad word. Mommy's going to get really mad at you."

The future Mrs. Kardashian revealed in the Instagram caption that she's proud of her hubby-to-be's ability to co-parent King. "But overall I'm so happy & blessed to have Robert here willing to help teach King right from wrong," she wrote.


Sounds like the only Kardashian brother is ready to be a daddy! And good thing too because Chyna's due date — this November — is approaching quickly.

rob kardashian blac chyna – snapchat

Rob and Chyna.

Aside from welcoming their own bundle of joy in upcoming months, Chyna and Rob clearly have their hands full with King. In fact, viewers can look forward to seeing the couple flexing their parenting skills on their E! reality TV series Rob & Chyna as King is expected to make appearances on the show.

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"You guys are going to definitely see King on Rob & Chyna because he is a part of our lives. That's my baby, it's going to be his," Chyna said during a recent Facebook Live video promoting the series.