Cameron Diaz's husband Benji Madden gushed over his new family in a sweet post.

The actress and her Good Charlotte rocker husband announced they were new parents to daughter Raddix last month in an Instagram post and, taking to the platform again, the 40-year-old guitarist reflected on his new role as a dad.

“My Wife and Daughter fill me up with so much gratitude,” Benji wrote alongside a drawing of some roses. “Everyday, I feel so lucky.”

He added: “Just wanted to say it out loud!!! Much Love & Best Wishes.”

The tot, who was born on 30 December, is named Raddix Chloe Wildflower Madden.

"She has instantly captured our hearts and completed our family. While we are overjoyed to share this news," wrote Diaz as she announced the happy news with a joint statement.

She also said the couple has a "strong instinct to protect our little one's privacy", and refused to share any further information or photographs online.

"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... Sincerely, Cameron & Benj," the social media statement concluded.

Cameron and Benji wed in 2015, and Raddix is the couple's first child.