Hilary Duff’s son already has a creative name picked out for his sister

Hilary Duff’s 6-year-old son, Luca, is getting excited about his new baby sister — so much so, he’s already picked out a name for her.

The “Younger” star, 30, swung by “The Late Late Show” on Monday and told host James Corden that while Luca wasn’t initially thrilled to hear he’d be a big brother, that’s recently changed.

“The beginning was a little, a little a … he was surprised. And now he’s warming up to the idea,” said Duff, who revealed last week that she and boyfriend Matthew Koma, 31, were expecting their first child together.

When Corden asked about potential names for the baby, the “Lizzie McGuire” alum said Luca had picked out one he felt strongly about.

“We’re up for any kind of suggestions, but Luca thinks ‘Cofant Croissant’ is like, the coolest name,” she said, adding that Luca insists the two names go together. “When I just refer to it as ‘Cofant’ — and I’m like, ‘That would be so cool, no one at school’s going to be named ‘Cofant’!’ — he’s like ‘Croissant. Cofant Croissant.’ It goes together. There’s no separating the two.”

Duff admitted she found the name “concerning,” but Corden insisted such a unique moniker could only bring a child success. “No one’s ever working in a call center called ‘Cofant Croissant,'” he joked.

Of course, Luca has his own ideas of what his baby sister will be like.

“He told his friend at school the other day that he’s having a sister that’s part red-butt monkey,” Duff shared. “So we’ll see! It’ll be a first. That’ll be really cool.”

Watch the hilarious conversation in the video above!

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