The actress, 47, and musician, 40, happily announced the birth of their daughter Raddix on Instagram last Friday.
A source tells PEOPLE that Diaz and Madden welcomed Raddix “right before New Years in Los Angeles.”
“You can tell they are just the happiest,” the source says. “It’s very emotional for them.”
The new parents shared the baby news with a joint statement on Instagram. “Happy New Year from the Maddens!” the couple wrote. “We are so happy, blessed and grateful to begin this new decade by announcing the birth of our daughter, Raddix Madden. She has instantly captured our hearts and completed our family.”
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Their statement concluded, “While we are overjoyed to share this news, we also feel a strong instinct to protect our little one’s privacy. So we won’t be posting pictures or sharing any more details, other than the fact that she is really really cute!! Some would even say RAD 🙂 From our family to all of yours, we’re sending our love and best wishes for a Happy New Year and Happy New Decade.”
A source recently told PEOPLE that Diaz and Madden had wanted to expand their family since getting married in January 2015.
“Cameron really wanted to be a mom,” the source said the star. “Cameron and Benji were hoping they would be blessed with a baby.”
Their daughter’s arrival comes five months after Diaz opened up about her life with the Good Charlotte rocker and how they find peace away from the spotlight.
“Getting married to him was the best thing that ever happened to me. My husband’s the best,” Diaz told InStyle in August for their special 25th-anniversary issue. “He’s the greatest human being, and he’s my great partner. Marriage is certainly hard, and it’s a lot of work. You need somebody who’s willing to do the work with you, because there’s no 60-40 in marriage. It’s 50-50, period. All the time.”