When Margo Seibert joined the cast of the Broadway show “In Transit” this past fall and learned that the script called for an infant, she knew who’d be perfect for the part: the theater veteran Twan Baker.

He made his debut in a 2009 production of “Into the Woods,” as the newborn offspring of the Baker and the Baker’s Wife at the Pittsburgh Civic Light Opera. Since then, Twan — an 18-inch-long, 10-pound (just a guess) blue-eyed doll with an alert expression — has appeared in five Broadway shows, including “Cinderella,” “The Bridges of Madison County” and “Honeymoon in Vegas.” James Earl Jones cuddled him this summer in “God Bless You, Mr. Rosewater” in an “Encores!” Off-Center production.

And yes, that was Twan as Marie (he’s clearly versatile), the love child of George and Dot in the recent Encores! rendition of “Sunday in the Park With George.” (Word is he’ll be auditioning to join the human stars Jake Gyllenhaal and Annaleigh Ashford when the show moves to Broadway in the spring.)