"Our beautiful little girl Poet Lake Palmer arrived Friday night on April 12th. She is pure magic, we feel like we are in a dream," Teresa wrote, alongside a special photograph of her breastfeeding her little girl, via her Instagram account.
Mark shared his own post about their new arrival, plus some new ink to commemorate her!
"I whispered her a poem as soon as she was born. Our beautiful baby girl Poet Lake Palmer has arrived. We’re all in total bliss...," he captioned his Instagram post, which revealed her name tattooed on his neck, just above the collarbone.
Actress Jenna Dewan commented, "Congratulations my love," while Jaime King wrote, "We can't wait to meet the newest member of the family we love you so much."
Teresa and Mark are already parents to two boys, Bodhi, five, and Forest, two, while Teresa plays stepmother to Mark's eldest, another son named Issac, 11, whom he shares with actress Frankie Shaw.
No word on why Poet took her mother's surname, while their sons go by Webber.
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