12/19/2012 02:59 pm ET

James Marsden Welcomes Son William Luca

James Marsden is a father for the third time.

Brazilian model Rose Costa delivered a son, William Luca Costa-Marsden, on Friday, Dec. 14 in Los Angeles, People has learned.

The "30 Rock" star, who briefly dated Costa after his split from wife Lisa Linde in 2011, picked the name and is being very supportive, a source tells PEOPLE.

Read more on celebritybabies.people.com