Morena Baccarin is pregnant with her Gotham costar Ben McKenzie's baby, her rep confirms to Us Weekly Credit: Gabriel Olsen/FilmMagic

Holy Gotham! Morena Baccarin is pregnant and expecting a baby with her Gotham costar Ben McKenzie, both of their reps confirm to Us Weekly.

Baccarin, 36, and The O.C. alum, 37, play Dr. Leslie Thompkins and Detective Jim Gordon, respectively, on the series Gotham. Their characters are also dating and living together.

The couple — who have yet to publicly confirm their relationship — attended the 67th Primetime Emmy Awards on Sunday, Sept. 20. "They weren't acting coupley or anything!" an insider told Us.

This will be the first child for McKenzie and the second for Baccarin. The Homeland alum shares 23-month-old son Julius with her estranged husband, Austin Chick, who filed for divorce back in June. According to TMZ, Baccarin filed court documents on Thursday in New York asking for full custody. While the judge granted her joint custody, her son will live with her in New York, and Chick will be able to visit him once a month for eight days.

In related baby news, Us broke the news on Thursday that McKenzie's former O.C. costar Adam Brody and his wife, Leighton Meester, welcomed their first child together last week.

Watch an amazing throwback clip from the time Ryan Atwood (McKenzie) and Seth Cohen (Brody) met for the first time on The. O.C. above!

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