Steve Martin has become a father for the first time at the age of 67.The movie funnyman and his wife Anne Stringfield, 41, welcomed a baby into their lives in December and although they have managed to keep their happy news a secret the couple have been spotted doting on the tot near their Los Angeles home.A source told the New York Post newspaper: "They've had a baby, and how they kept it a secret nobody knows. Steve's very private. They are thrilled. They worked hard to have the baby." Steve - who played a father of 12 in the comedy movie 'Cheaper By The Dozen' - and Anne married in July 2007 after three years together.The ceremony took place at Steve's Los Angeles home with former Nebraska Senator Bob Kerrey presiding over the ceremony, while 'Saturday Night Live' creator Lorne Michaels was best man.Guests, who included Tom Hanks and Diane Keaton, did not know the couple were getting hitched and instead thought they had been invited to a party.A representative for the 'Parenthood' actor would not comment on the baby news.