Oct 21, 2008, 9:50 GMT
Gillian Anderson welcomed a baby boy into the world on October 15, her representative has confirmed.
New mother: Gillian Anderson arrives at the UK Premiere of US director Chris Charter's film 'The X-Files: I Want to Believe' - EPA/DANIEL DEME
'The X-Files' star - who has a one-year-old son Oscar with boyfriend Mark Griffiths and a 13-year-old daughter Piper from a previous marriage - gave birth to Felix Griffiths, who weighed 6lbs 15oz, in London earlier this month.
Both mother and baby are said to be doing well and Gillian and Mark are "thrilled" with their new arrival.
Gillian, 40, recently revealed she doesn't regret her decision to move from Los Angeles to London, as she believes it was the right choice for her family.
She said: "By moving to London, I removed myself from the madness of the entertainment industry. I love the city, the culture, and the opportunity to bring my children up in a more sane environment.
"One of the great things about living in Europe is that there's no stigma about jumping between different media - I get to do film, theatre and, occasionally, television."
The actress previously admitted she was in no rush to lose weight after giving birth, and was making the most of being pregnant.
She said: "I'm not really craving anything, but there's the lazy part of me that thinks, 'What's the point in working out until I have the baby?' Then we'll actually do something!"
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