Ellen DeGeneres has a good track record when it comes to guessing details about celebrities’ yet-to-be-born babies – and so was the case with Natalie Portman‘s second pregnancy.

It’s been over a year since the Annihilation actress, 36, made her last appearance on The Ellen DeGeneres Show in December 2016, and since then Portman has welcomed another child with husband Benjamin Millepied.

Recalling her pregnant body as “enormous” during Wednesday’s episode of the NBC daytime show, the Oscar winner congratulates host Ellen DeGeneres on correctly guessing the gender of daughter Amalia, who was born in February 2017.

And DeGeneres had even put money on it.

“You wouldn’t tell anybody what the sex was and I guessed. And you really didn’t know,” she reminds Portman, who reveals: “I maybe did but I maybe didn’t want to tell everybody in the world. I still made the bet because I thought it would show either way.”

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PEOPLE confirmed in early March that Portman and Millepied had welcomed their baby girl. The couple, who married in 2012, is also parents to son Aleph, now 6.

“But I kept good on my bet. Ellen bet $1,000 … You were confident, you were right to be confident, it’s a girl!” says Portman, who reveals that she made a $1,000 donation to the Ellen DeGeneres Wildlife Fund.

RELATED: Natalie Portman Returns to Work Eight Weeks After Giving Birth to Daughter Amalia

Though Portman and Millepied, who met on the set of the 2010 hit thriller Black Swan, are notoriously private about their family life, the actress opened up about how parenthood has changed her for The New York Times’ T Magazine.

“ made me much calmer under stress, because there’s that weird parent thing you develop, that when things get really bad, your voice gets calm and your blood pressure slows, and you can make everything okay again,” Portman wrote at the time.

Annihilation hits theaters Feb. 23.