'KUWTK': Kourtney Kardashian says she could change her kids' last names so Blac Chyna won't have the sole Kardashian heir

"Keeping Up With the Kardashians" Katch-Up S12, EP. 8
"Keeping Up With the Kardashians" Katch-Up S12, EP. 8

Awkward! It looks like the Kardashians don't want Blac Chyna to carry on their family's name. On Sunday's episode of Keeping Up With the Kardashians, the family was deeply offended when they learned via social media that Rob Kardashian had proposed to Blac Chyna without bothering to tell them.

In previously released clips, fans saw Rob's sisters' stunned reactions to the news, but in Sunday's episode, Kourtney Kardashian took it a step further while on the family's trip to Vail.

WATCH: The Kardashians React to Being Blindsided by Rob's Engagement to Blac Chyna on 'KUWTK': 'Why Would We Congratulate Him?'

After offering to be the first one to reach out to Chyna, calling herself "the rational one," the eldest of the Kardashian-Jenner clan got personal at dinner while talking to Kylie Jenner's then-boyfriend (and Chyna's ex) Tyga.

"She's gonna carry on the legacy, like if she has a boy," Tyga said of the now-pregnant Chyna.

"I could change my kids' last names," Kourtney replied, referencing her three kids – Mason, Penelope, and Reign Disick.

"What the f**k, I'm sitting right here you sick f**k!" Scott replied.

WATCH: Kris Jenner 'In Shock' Over Rob Kardashian's Engagement to Blac Chyna on 'KUWTK': 'He Should've Told Me First'

Clearly the father of three was not pleased by Kourtney's suggestion. She went on to clarify that she "could change" her kiddos last names "so that she couldn't have the last name."

Scott replied, "What the f**k is wrong with you?" to which Kourt insisted, "It's a joke!"

This isn't the first time one of the famous family has toyed with a possible name change. Momager Kris Jenner considered reverting back to the Kardashian last name even while she was still married to her now-ex Caitlyn Jenner.

Though the family seemed upset by Rob's proposal, there's a chance they could still come to the wedding. In the words of Kourtney: "How many weddings have we been to in this family and they don't mean s**t so let's all get it over with."

RELATED: Rob Kardashian & Blac Chyna's relationship through the months