From Superbad to super dad!

Jonah Hill welcomed his first baby with girlfriend Olivia Millar,Kacper Sobieski his rep confirmed to People June 2. The baby's sex and name have not been revealed.

The news comes amid another big milestone in Jonah's family. His sister Beanie Feldstein married producer Bonnie-Chance Roberts on May 20 in upstate New York, though Jonah wasn't seen at the ceremony in any of the Vogue photos. 

The Don't Look Up star was first linked to Olivia—a co-founder of the online vintage clothing retailer Chasseresse—in August 2022, when the two were spotted kissing on the beach in Malibu, Calif. A month after the sighting, Jonah embarked on a road trip with Olivia and her family, including her older sister Raychel Roberts, up the coast to Santa Barbara. 

The couple appeared to have taken their relationship to the next level by the new year. On Jan. 10, Jonah and Olivia were seen shopping at a kids' clothing store during a trip to Hawaii. At the time, the actor looked ready for the beach in a casual tee and swimming trunks, while the fashion maven sported a white bikini top and long, flowing purple skirt. 

Jonah has largely kept quiet about his love life since his breakup with surfer Sarah Brady last year. In fact, the 21 Jump Street alum deactivated his Instagram account last August, shortly after announcing that he will not be doing press for his movies moving forward to protect his mental health.

"Through this journey of self-discovery within the film, I have come to the understanding that I have spent nearly 20 years experiencing anxiety attacks, which are exacerbated by media appearances and public facing events," he explained in an open letter obtained by E! News ahead of the release of Stutz, Jonah's documentary about his psychiatrist Dr. Phil Stutz. "If I made myself sicker by going out there and promoting it, I wouldn't be acting true to myself or to the film."

Though Jonah acknowledge that he usually would "cringe" at public statements such as his letter, he believed stepping away from the spotlight was the right move in his mental health journey.

"With this letter and with Stutz, I'm hoping to make it more normal for people to talk and act on this stuff," he added. "So they can take steps towards feeling better and so that the people in their lives might understand their issues more clearly."

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