Morgan and her estranged husband, Michael Kopech, welcomed a baby boy on Jan. 29.
Morgan revealed River's name in the post, alongside a photo of his tiny hand.
"The most challenging, beautiful experience of my life. On January 29th, Michael & I Welcomed our beautiful baby boy River into the world," Morgan wrote. "Words cannot describe this kind of love. We are enjoying this time home with him, being present, & giving him all the lovin in the world🤍👶🏼 Becoming parents is the most rewarding gift in the entire world. Thankyou God. 🙏🏽 Isaiah 66:9."
Fans and friends sent congratulations in the comments, while Morgan's Riverdale co-star, Lili Reinhart, wrote, "His aunts and uncles can't wait to meet him!!"
Morgan announced she was pregnant on Instagram on July 24, and made no mention of Kopech, whom she married in January 2020. Days later, news broke that Kopech had filed for divorce from Morgan on June 19. Kopech, a professional baseball player, also took time off from playing for the Chicago White Sox this season due to "personal reasons."
Meanwhile, Morgan wrote of her pregnancy, "This little guy has already brought me so much happiness and a feeling of such a greater purpose. I cannot wait to meet you!! ... Lil one you were made with so much love & already exude a light so strong it warms my belly. Thank you God for this blessing ☺️ I'm just so happy & can't wait to dedicate everyday to being the best mommy I can be ♥️."
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