It’s … Dylan’s baby!
“Welcome to my beautiful little grand-daughter, Evangeline,” Mia, 71, wrote next to a shot of the sleeping baby, wrapped in blankets and wearing a hospital cap.
“Born 3 hours ago to Dylan Farrow and her husband, Dana,” added the proud new grandmother.
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Dylan’s brother Ronan Farrow, who is Mia’s biological son (Dylan was adopted at 2 weeks old), also took to social media to share his pride over Evangeline’s birth.
“Uncle x12,” Ronan, 28, wrote next to a photo of himself holding his newborn niece.
Dylan announced her pregnancy in April, when she and Mia attended TIME’s 100 Gala in New York City.
“I picked a name, but my husband would kill me if I told you,” Dylan told PEOPLE at the time, revealing that she would be having a girl. “He wants it to be a secret.”
“I have nine grandchildren, but I’m excited about this one,” Mia added of her soon-to-arrive 10th grandchild.
— Jen Juneau