The troubled actor - who was charged for DUI (driving under the influence) in September 2002, and subsequently checked into Connecticut's Silver Hill rehabilitation centre - welcomed the baby girl with his partner Clytie Lane in Los Angeles last Wednesday (03.10.07).
A representative for Nick said: "The baby girl, who has yet to be named, weighed 7lbs and 13oz at birth. Both mother and daughter are doing well."
The actor first met the 38-year-old British fitness instructor when she came to his home to teach him Pilates.
Nick, who has been married and divorced three times, also has a 20-year-old son, Brawley, from his marriage to Rebecca Linger.