Khloe Kardashian at the Good American launch event at Nordstrom at the Grove on Oct. 18, 2016, in Los Angeles. Credit: Steve Granitz/

He’s not sweatin’ it. Khloé Kardashian spoke exclusively with Us Weekly about brother Rob Kardashian’s laid-back attitude leading up to the birth of his first child with his fiancée, Blac Chyna.

“Rob is fine. He says he's really fine and calm about it, but I was like, ‘It's OK if you're nervous!’” Khloé, 32, told Us at the Tuesday, October 18, presentation for her brand-new Good American denim line. “I think anybody would be nervous. But he seems super chill about it, so that's good.”

For her part, the Strong Looks Better Naked author is looking forward to welcoming another bundle of joy into the Kardashian clan. She told Us that Chyna, 28 — who is expecting a little girl — is telling the Keeping Up With the Kardashians crew that her daughter belongs to the entire family.

“Chyna keeps joking like, ‘This is our baby!’ Like with me too,” the E! personality shared. “So it's like, I haven't been getting prepared, but I'm like, ‘Should I be putting a nursery in my house too?’ Chyna's like, ‘Are you so excited? We're having a baby soon!’ And I'm like, ‘Wait, are you kidding or am I really having a baby with you?’”

Not that she minds. According to the newly minted fashion designer — who regularly dotes on sisters Kourtney and Kim’s combined five kids — Auntie KoKo is a title she is proud of.

“I love them all. It's such a great thing to have another baby just to have with us, it's great,” she told Us of Rob and Chyna’s daughter-to-be, due in early November. “But at first, they're just with the mom, like you forget about them.”

She added: “They’re never around ‘cause the other kids are so rough, they're like all toddlers, you know? I just want to fast-forward!”

As previously reported, Chyna — who is already mom of King Cairo, 3, with ex-fiancé Tyga (Kylie Jenner’s current beau) — announced that she and Rob were having a baby back in May, one month after the pair got engaged.

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