Hilary Duff and boyfriend Matthew Koma have welcomed a baby girl into the world.

The 31-year-old shared the sweet news on Instagram Monday, announcing their daughter, Banks Violet Bair, was born on Oct. 25 at their home.

"This little bit has fully stolen our hearts," Duff wrote in her post. "She joined our world at home on Thursday afternoon and is absolute magic."

The post includes an adorable photo of the couple cradling their newborn with loving smiles.

Koma shared the same photo on Instagram, writing in part: "We welcome a beautiful daughter, little sister, and best friend for life. Could not possibly be more grateful for our growing family and for the [peach] who makes it all possible. Cloud ten."

Banks is the couple's first child together.

Duff shared the news of her pregnancy back in June on Instagram, stating they were expecting "a little princess."

The "Younger" actress is also a mother to her 6-year-old son, Luca Cruz, from her previous marriage to Mike Comrie.

Koma and Duff have been dating since 2017.