The 32-year-old actress welcomed her second child, daughter Elle, with her husband, Andrew Joblon, on Saturday.
Holt and Joblon married in August 2018 and also have a 17-month-old son, James. Holt shared news of her baby girl's birth Sunday on Instagram.
"She's here. Our sweet girl, Elle. After 27.5 hours of labor, she flew into the world and expanded our hearts. We are so grateful for our healthy baby and cannot wait for her to meet her big brother," she wrote.
Joblon confirmed the news with a photo on his own account.
"Baby Elle has finally made her appearance after 27.5 hours of labor. @claireholt again proved to me she is my hero and a true warrior - I love you with all my heart," Joblon captioned the post. "Thank you so much for birthing this sweet little girl in a challenging year."
"All the women out there, no debate from me, you guys are the superior gender and it's not even close!! 9.12.2020 - my heart is full," he wrote.
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