The 33-year-old actress and her fiancé, Matt Rosenberg, welcomed their second child, a baby girl, on Tuesday.
Duff announced the exciting news via Instagram on Thursday, with an adorable picture of her eldest child, 3-year-old daughter Ryan, cradling the newborn. Her name? Lulu Gray!
"She arrived June 5th, and brought all her magic with her!" Duff captioned the cute photo. "Ryan is the happiest big sister & we are finally a family of 4! ?Meet our littlest one... Lulu Gray Rosenberg!"