Rumer Willis welcomes 1st child with boyfriend Derek Richard Thomas

"You are more than we ever dreamed of," Willis and Thomas wrote on Instagram.

Rumer Willis is a mom.

On Tuesday, the actress, 34, and her boyfriend Derek Richard Thomas, a musician, shared a joint Instagram post featuring a photo of their newborn baby.

"✨Louetta Isley Thomas Willis ✨ You are pure magic 🌱," the couple wrote in the caption.

"Born at home on Tuesday April 18th," they added. "You are more than we ever dreamed of ✨."

Rumer Willis first announced she was expecting in December, posting a photo of her belly on Instagram.

Her sisters and mother Demi Moore have supported her on her journey to motherhood.

In December, Moore shared a photo of herself at one of Rumer Willis' ultrasound appointments. Moore's daughters Tallulah Willis and Scott LaRue Willis were also seen in the photo.

At the time, Moore wrote that it was an "honor to witness" her daughter's journey to motherhood.

"Saying hello to the little nibblet!! Overjoyed for you, my sweet Rumer," she wrote in the caption. "It's an honor to witness your journey into motherhood, and can't wait to welcome this baby into the world!"

Moore shares all three daughters with actor Bruce Willis. Bruce Willis also has two daughters with his wife Emma Heming Willis, 8-year-old Evelyn Penn and 11-year-old Mabel Ray.

Louetta is Moore's and Bruce Willis' first grandchild.