Morena Baccarin sports a baby bump on set of Gotham 2 -- see the photos of the pregnant star Credit: Gabriel Olsen/FilmMagic; Jose Perez/Splash News

Baby on board! Pregnant star Morena Baccarin was photographed on set of Gotham shooting scenes with her costar and boyfriend, Ben McKenzie, with a visible baby bump on Sept. 18. As previously reported by Us Weekly, the Homeland star, 36, is expecting a child with the O.C. alum, 37.

However, it’s unclear if Baccarin's Gotham character, Dr. Leslie Thompkins, is also pregnant in Season 2, as the actress sported a less noticeable bump at the 2015 Emmys on Sunday, Sept. 20. Their characters are, however, dating and living together on the hit show.

This will be the first child for McKenzie. Baccarin is already mom to a 23-month-old son named Julius, whom she shares with estranged husband Austin Chick.

According to TMZ, who first revealed the costars were expecting, Baccarin has been awarded joint custody of Julius, who will split time between his parents but reside in NYC with his mom.

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

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