Cameron Diaz and Benji Madden Enjoy Date Night at Rob Lowe’s Birthday Party After Welcoming Baby Son Cardinal

Cameron Diaz and Benji Madden had a mom and dad's night out!

The couple were among the many A-List stars who gathered in Santa Barbara, California, on Saturday night to celebrate Rob Lowe's milestone 60th birthday.

As seen in photos from the event, the two were dressed casually for their first public outing since they announced the arrival of their son, Cardinal Madden on Friday.

Madden, 45, sported a black denim jacket and a black baseball cap as he stood close to his wife Diaz, 51, who wore a black jacket over a black top while carrying a brown box and flower branches in her hands.

They celebrated Lowe together with other A-list couples including Gwyneth Paltrow and her husband Brad Falchuck, Katy Perry and Orlando Bloom, Ellen DeGeneres and Portia de Rossi and Adam Levine and Behati Prinsloo.

The Good Charlotte musician and the Vanilla Sky actress revealed the birth of their baby son via an Instagram post, featuring an abstract drawing that included the words, "A little bird whispered to me."

"We are blessed and excited to announce the birth of our son, Cardinal Madden❤️🙏. He is awesome and we are all so happy he is here!" the post's caption read. "For the kids' safety and privacy we won’t be posting any pictures - but he’s a really cute ☺️. We are feeling so blessed and grateful🍀. Sending much love from our fam to yours 🙏❤️. Best wishes and Good Afternoon!! 🤘⚡️."

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A day after sharing their baby news, the spouses — who are also parents to 4-year-old daughter Raddix — joined Lowe's family, including his wife Sheryl Berkoff, and their two sons, John Owen and Matthew, at the 9-1-1: Lone Star actor's birthday party.

Jennifer Aniston, Zoe Saldaña, Amy Poehler, Kevin Costner and Robert Downey Jr. were also among the celebrity guests helping Lowe celebrate turning 60.