"You gotta understand, she does not share with Saint, she does not hardly talk to Saint, so that was such a big moment in my household."
She previously alluded to their rivalry back in October, saying "Obviously North loves Saint, she just is still jealous.
"She needs to still get it together and warm up and like be a little bit nicer, but I think she is getting there. I saw glimmers of hope like a week ago. She's not like harmful. She's not like hurting him or anything."
The mother-of-three gushed over her son in a tweet earlier this year, saying that the little guy is a genius.
"Guys I have to say my son is a genius! He's two years old and knows how to spell gargantuan. Had to brag for a sec," she shared on Twitter.
Kim also revealed to Ellen that she wanted to name her baby daughter Jo in tribute to her beloved grandmother, Mary-Jo Shannon.
The Keeping Up With The Kardashians star explained she wanted Chicago's name to be one syllable like daughter North, four, and son Saint, two, and so the moniker "kind of messes" with her.
"We were gonna name her Jo because my grandma Mary Jo or we were gonna go with Grace and then it was Chicago," she said.
"But you told me you wanted a one syllable," Ellen said in the teaser clip. "When I was pitching names you said you wanted one syllable."
"And I did," Kim responded.
"So... Chicago is not one syllable."
"Yeah, it kind of messes with me, I'm not gonna lie. I really like the one syllable thing," Kim admitted.
Ellen went on to ask: Because Kanye wanted Chicago? Because he's from there?
"I don't even know ... obviously because he's from Chicago but that is a place that made him."