Terri, who is best known for playing Ruth Osbourne in the Channel 4 soap, welcomed son Kylan Jones Marley with husband Sean Marley at a Merseyside hospital, according to Click Liverpool.
The tot weighed in at 8lbs 4oz.
The couple, who tied the knot in 2004, already have one child, three-year-old Caiden Ajay Marley.
A source said: "Terri and Sean are delighted. They've always wanted a big family and they couldn't be happier with the new arrival.
"Sean held her hand throughout the delivery and mum and baby are doing well.
"Terri will probably be released from hospital late this evening, she can't wait to get home with the new tot."
Terri, 36, starred in Hollyoaks between 1995 and 2001, and returned for a brief stint in 2003.