It's a girl!

Former O.C. actor Chris Carmack and fiancée Erin Slaver have welcomed a baby girl — and the proud couple is already gushing over their newborn.

"In my life, I never imagined I'd experience something so beautiful," the new mom wrote on Instagram, sharing a photo of her daughter lying on her chest. "I couldn't have made it through naturally without [doula Brittany Anderson] and [Chris] by my side. We are completely in love with our 2 day old, sweet baby girl."

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The pair met on the set of Nashville when Erin worked as a backup singer for Hayden Panettiere's character, Juliette Barnes, and became engaged in March of this year. The new parents have yet to release the name of their baby girl.

Congratulations to the growing family!