“I'm with her. Introducing Paloma Michaela Giles. The future is female,” the 35-year-old actress wrote, accompanying the caption with the first photo of her newest addition wearing an “I Voted” sticker.
Paloma joins older sister Eliza, whom the couple welcomed in July 2012.
ET broke the news in August that Scorsone -- already showing a huge baby bump -- was pregnant with her second child, and she revealed they were choosing to keep the baby’s sex a secret. “We’re kind of not [saying],” she said at the time.
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Scorsone isn’t the only Grey’s star welcoming a new bundle of joy. Her co-star, Camilla Luddington,announced in October that she and her longtime beau, actor Matt Alan, were expecting their first child in 2017.