The actor has confirmed reports that he's expecting his first child with Gotham co-star Morena Baccarin, which surface djust a few days after it emerged they were dating.
Ben, 37, and Morena, 36, met on the set of the thriller TV show but have kept their relationship away from the spotlight. It was only revealed when they were seen holding hands over Emmy Awards weekend in LA.
Ben confirmed the news by retweeting a message his sister posted to Twitter reading: "Couldn't be happier for @ben_mckenzie and @missmorenab. Welcome to the family, Morena! Also... I'M GONNA BE AN AUNT."
Morena, who has also starred in Homeland, has a son called Julius from her previous marriage. Her estranged husband Austin Chick filed for divorce in July after three years of marriage.
Ben's baby news comes after his former The O.C. co-star Adam Brody became a first-time father. He and wife Leighton Meester are reported to have welcomed a baby girl in August.
Their fellow co-star Rachel Bilson gave birth to her first child, Briar Rose, in November 2014.
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