Born on Dec. 14, 2012, William Luca Costa-Marsden is Marsden's third child, whom he shares with former girlfriend Rose Costa. In a 2014 interview with ABC News, James said he wasn't worried when he had William Luca — who's seven years younger than his daughter — that he'd forget about taking care of a newborn or changing diapers. "Once you become a father . . . it's like riding a bike — once you learn it, you sort of got it," he said.
From Costa's Instagram, it seems she and William Luca split their time between Brazil and the United States. James has pulled back from sharing photos of his kids on social media in recent years, but William Luca was with his siblings at the "Sonic 2" premiere in 2022. He also attended a family screening of "Sonic" in 2020 with his dad.
