"We are on cloud nine and so happy she is finally here! Thank you to everyone for all of their love, support, & well wishes," Duff and her fiancé, Matt Rosenberg, told the magazine.
This is the first child for Duff and Rosenberg, who announced back in December that they were expecting a daughter together. Since then, Duff has kept fans and readers up to date on her pregnancy through her blog, where she posted photos as well as the recipes she was making to satisfy her pregnancy cravings. And luckily for the first-time parents, baby Ryan already has a playmate nearby—Duff's sister, Hilary Duff, is mom to 3-year-old son Luca.