The Little Miss Sunshine actor and Wildlife director, 34, confirmed on The Tonight Show Wednesday night that he and his longtime girlfriend Kazan, an actress and screenwriter, welcomed a daughter about eight weeks ago.
“I’m so tired and I’m so in love,” he told Jimmy Fallon of becoming a father for the first time. “It’s so extreme. Your heart has gone supernova in one sense.”
“And then we landed from London last week and she cried for like 24 straight hours and you kind of just want to walk through a wall,” Dano joked.
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Dano and The Big Sick star Kazan — who co-wrote the screenplay for Wildlife alongside Dano — have been together for over a decade.
The notoriously private couple have been photographed at a variety of events over the years, and even starred together in multiple films like the 2012 dramedy Ruby Sparks, written by Kazan, 35.
“For me the best thing that Zoe did was not write a film about our relationship or write us as characters,” Dano told The New York Times in 2012 of the latter film. “Calvin and Ruby are Calvin and Ruby, they’re not Paul and Zoe.”
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“Luckily, when I watch the film, I’m not thinking about us,” he added. “I don’t see us. I don’t see the girl I see in our apartment. I see Ruby.”
Wildlife is playing in limited theaters nationwide now.