The 35-year-old Pretty Little Liars alumn, who only revealed on Saturday that she gave birth two weeks ago, announced that she had named her daughter Rome in honor of her late grandmother.
The actress already shares her two-year-old daughter Atlas with her longtime partner Matte Babel, 40.
In the photo, the former You actress appeared to be topless while cuddling with Rome, who already had an impressive head of dark hair.
The screen star wore a gold necklace around her throat reading Rome in Old English Text.
"Losing the most important person in my life in the same year I welcomed my second daughter has shifted everything for me, but one thing remains steady in my soul — I’m certain they spent time together and that brings me peace and joy," she wrote in her caption.