FIRST OFF . . .

Sources close to writer-director Woody Allen and actress Mia Farrow said Sunday that Farrow gave birth over the weekend to Allen’s first child, a 9-pound boy that they named Satchel. The hospital was kept a secret, but a source quoted Allen as telling close friends that Mia and Satchel were both doing well. Tony Roberts, an actor who has appeared in several of Allen’s films, reportedly announced Satchel’s birth at Elaine’s--a restaurant that Allen frequents--early Sunday morning. Allen could not be reached Sunday for comment.