The Younger actress, 30, is expecting a baby with boyfriend Matthew Koma, 31, and the couple is competing for the biggest belly.
On Friday, Duff shared an elevator selfie where the two compared their stomachs.
“I win,” she wrote.
Duff revealed in June that she and Koma were expecting their first child together, a daughter.
“Guess what guys! @matthewkoma and I made a little princess of our own and we couldn’t be more excited!!!!!!” she posted on Instagram.
The couple confirmed that they were back together late last year after splitting briefly in March 2017.
Duff is also mom to son Luca Cruz, 6, with ex-husband Mike Comrie. Though he’s “warming up to the idea” now, Duff said that Luca wasn’t thrilled about his baby sister on the way at first.
“The beginning was a little … he was surprised,” she said during an appearance on The Late Late Show with James Corden in June. Now that some time has passed, Luca is working on coming up with a name.
“Luca thinks ‘Cofant Croissant’ is like, the coolest name,” Duff said, adding that he was insistent about his pick. “There would be no confusion. And 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.”
This article originally appeared on PEOPLE
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