Will Arnett and Girlfriend Alessandra Brawn Welcome Son Alexander Denison
The new baby boy joins Will Arnett's sons Abel, 9½, and Archie, 11, with ex-wife Amy Poehler, plus Alessandra Brawn's son Nash
Will Arnett is a father of three.
" 'Denny' is home and everyone is doing well," the rep shares.
PEOPLE confirmed Brawn's pregnancy in February.
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Arnett and Brawn, the former CEO of clothing brand Chapel, reportedly began dating last year and attended the 2019 Creative Arts Emmys together last September.
"I just tell them because of the nature of our jobs people see that more than if I was an accountant," he said at press conference in New York while promoting Teenage Mutant Ninja Turtles: Out of the Shadows.
"People are familiar with your work so they know who you are and they want to, I guess, participate in that or whatever," Arnett added.
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"Never has the idea of celebrity meant less because we live in a day and age where you’re famous for no definitive skill set other than being on social media," he continued. "People are like, 'Oh, he's an Instagram star.' But for what? It used to be you had to do something … it's bizarre."
Arnett added, "Even though there are elements that are kind of weird, I always appreciate when people are fans and like the stuff. I'm a fan of a lot of other people myself."
"I appreciate when people compliment you and let you know. I don't make it in a vacuum so nobody watches it," he said.