Will Arnett, Girlfriend Arielle Vandenberg Make Red Carpet Debut at 2015 Golden Globes Party After Ex-Wife Amy Poehler Hosts: Photo

Will Arnett and girlfriend Arielle Vandenberg
Will Arnett and his girlfriend, actress Arielle Vandenberg, made their red carpet debut at a party for the 2015 Golden Globes on Sunday, Jan. 11, after his ex-wife Amy Poehler co-hosted the awards show -- see the photo Michael Kovac/Getty Images for Moet & Chandon

Big night out! Will Arnett and his new girlfriend Arielle Vandenberg made their red carpet debut at an after-party for the 72nd Annual Golden Globes Awards on Sunday, Jan. 11. The couple appeared smitten with each other on the red carpet after the show, which just so happened to be co-hosted by the actor's ex-wife, Amy Poehler.

Us broke news earlier this month that Arnett, 44, and the redheaded, turned blonde actress, 28, are an item. After splitting from Poehler in September 2012 following 10 years of marriage together, Arnett went on to date celebrity chef Katie Lee and producer Erin David.

tina and amy hosting
Tiny Fey and Amy Poehler host the 72nd Annual Golden Globe Awards held at the Beverly Hilton Hotel on January 11, 2015 Paul Drinkwater/NBC

"She loves to laugh," a source previously told Us of Vandenberg. "The past few girls haven't been fun enough for him, he's a child at heart."

Will looked sharp in a greaty suit and Johnston & Murphy cap toe shoes.

Poehler, for her part, has moved on as well. She's been dating comedian Nick Kroll since May 2013. Despite the amicable split (she and Arnett share sons Archie, 6, and Abel, 4), the Parks and Recreation star did admit that the breakup was painful at first.

"Getting a divorce really sucks," she told Hello! magazine back in October. "Imagine spreading everything you care about on a blanket and then tossing the whole thing up in the air. The process of divorce is about loading that blanket, throwing it up, watching it all spin, and worrying what stuff will break when it lands."

will and amy 2012
Amy Poehler and Will Arnett arrive at the 69th Annual Golden Globe Awards in 2012 Jeff Vespa/WireImage.com

As for how Arnett dealt with their broken marriage? "If going to the gym obsessively for eight, nine months was my way of dealing, then let that be my worst problem," he told Details magazine in June 2013. "Life is challenging, and I'd say that there's no guidebook." He added: "…I've found my happiness — which is my kids."

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