Greta Gerwig and Noah Baumbach have added to their family

Surprise Greta Gerwig is a new mom!

The Oscar-nominated actress, writer and director, 35, and her boyfriend, Oscar-nominated director Noah Baumbach, have welcomed their first child together, her rep confirms to PEOPLE.

Baumbach, 49, has a son, Rohmer, with his ex-wife, actress Jennifer Jason Leigh. This is Gerwig’s first child.

The two first met when Baumbach cast her to star opposite Ben Stiller in his 2010 film Greenberg, according to a 2013 New Yorker profile.

They’ve continued to collaborate in the films Frances Ha and Mistress America, which they both co-wrote together.

The couple has kept their relationship mostly private, but they attended the 2018 Golden Globe Awards and the Academy Awards together when Gerwig was nominated for directing and writing Lady Bird.

Gerwig spoke about forgetting to thank Baumbach in her Golden Globe speech while accepting the award for best original screenplay, telling The View he didn’t take offense.

90th Annual Academy Awards, Arrivals, Los Angeles, USA - 04 Mar 2018
Greta Gerwig and Noah Baumbach
| Credit: Chelsea Lauren/REX/Shutterstock

“I had an entire speech that I was going to give and I got up there and none of it came out,” she said. “I looked at Oprah and I was like, ‘It’s gone!’ I had a whole thing about him. He’s my favorite writer and my favorite first reader.”

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She added, “I got off stage and then as I was coming back to the table, he was already looking at me and he said, ‘Please don’t feel bad, please don’t feel bad!'”

In a 2013 interview with The Globe and Mail, Baumbach praised Gerwig, saying, “Greta’s one of the funniest people I’d ever met, both as an actor and a person, and she also has this incredible vulnerability.”

RELATED VIDEO: The Stars of ‘Lady Bird’ Loved Working with First Time Director Greta Gerwig

In the same interview, Gerwig spoke about their relationship, saying, “We never specifically talk about how it works.”

“In some ways, you don’t want to know too much about why; you don’t want to mess with it,” she said. “I’ve never been in a band, but I feel it must be what it feels like to write music with someone. I’m certainly not comparing myself to Lennon and McCartney, but they wrote great stuff on their own, and when they wrote together they made something greater than the sum of its parts.”

She added, “You can’t account for it; it’s almost like a third party enters into it.”