Ellen Pompeo - Lead 2016
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Congratulations are in order for Ellen Pompeo and her husband of nine years, Chris Ivery: The pair welcomed a new member into their family—their third child—the actress's rep confirmed to People on Thursday.

It may come as somewhat of a surprise that the parents have expanded their family since the Grey's Anatomy star and music producer did not previously announce that they were expecting. However, the couple tends to keep their private life very private, and only announced the birth of their now-2-year-old daughter, Sienna May, until two months after her arrival.

of Ellen Pompeo and Chris - LEAD
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With the new addition, little Sienna joins the couple's 7-year-old daughter, Stella Luna, in becoming a big sister. Although we don't know the baby's name or sex, "Everyone's doing great," Pompeo's representative tells People. (That sounds like an indication that the older siblings are more than pumped about the new playmate.)

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Pompeo joins two fellow Grey's Anatomy stars in the new mom arena: Camilla Luddington, who plays Dr. Jo Wilson, announced her own pregnancy in October of this year and Caterina Scorsone (aka Dr. Amelia Shepherd), who announced the birth of daughter Paloma Michaela Giles in November.

Congratulations to the happy couple, and new family of five!