11/19/2006 at 05:00 PM EST
Gillian Anderson gave birth to a baby boy on Nov. 1 in London, her manager Connie Freiberg confirms to PEOPLE.
This is Anderson's second child, her first with boyfriend businessman Mark Griffiths.
Oscar Griffiths was born three weeks early, but "both he and Gillian are just fine," says Freiberg.
"They are extremely happy – the entire family," she adds.
The former X-Files star, 38, who lives in London, plans to take a few months off before deciding on her next project. She was last seen in BBC's Emmy award-winning Bleak House.