The stunning star, 41, posted a shot of herself cozying up to her new addition, captioning the picture simply "#grateful" with a heart emoji.
In the image, Sims reclines on a bed as she holds the camera at arm's length. Wearing an unbuttoned white-and-pink pajama top, the Yes Man actress cradles her daughter Scarlett on her chest. The tiny baby has her eyes closed and rests her hand on her mother, reaching just below two delicate gold necklaces.
Sims, who gave birth to Scarlett May last Wednesday, March 25, looks beautiful in the sweet photo. With her blonde hair tucked behind her ears, she wears minimal makeup, giving a peaceful closed-mouth smile as she poses.
The model welcomed her new baby with her husband of four-and-a-half years, Scott Stuber. Sims married the filmmaker, 46, in September 2011, and they began their family with the birth of their first child, son Brooks, in June 2012.
The Sports Illustrated Swimsuit Issue alum first shared the news of Scarlett's arrival on Thursday. "We welcome Scarlett May Stuber into our family," she wrote on an adorable Instagram photo of the tot. "Our hearts are bigger with you here."
"Our little bundle of joy weighs in at 7.7 pounds and is 21 inches long," Sims added on her personal website last week. "Momma and baby are doing well. We are thrilled that the newest addition has finally arrived and we are so excited that we are now a family of four!"
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