BORN: Single mom Jodie Foster, 38, gave birth to a six-lb.-three-oz. boy, Kit Foster, on Saturday in Los Angeles. As with her older son Charles, 3, the Oscar winner will not identify the child's father . . . CHARGED: Ex-"Beverly Hills 90210" star Rebecca Gayheart has been charged with vehicular manslaughter for a June 13 accident that killed a nine-year-old boy crossing a Los Angeles street. The misdemeanor criminal negligence charge carries a sentence of up to one year in prison and a $1,000 fine. Gayheart will be arraigned Oct. 22 . . . ANNOUNCED: President Bush said that Washington's Reagan National Airport will reopen on Thursday, with "necessary safety precautions" to guard against an attack on landmark federal buildings by planes using the facility. Reagan is the only airport not to have reopened since the Sept. 11 hijackings . . . CHANGED: The Boston Symphony Orchestra will begin its new season, its 29th, Tuesday night with a special "America the Beautiful" performance. The shift marks the first time since President Kennedy's assassination in 1963 that world events have forced a program change for the BSO . . . CLOSED: Mademoiselle, a fashion magazine for young women that was first published in 1935, is shutting down for good. "Unfortunately, current economic conditions have produced a situation where . . . the magazine is no longer viable," Steven T. Florio, president of Conde Nast Publications Inc., said in a statement Monday. The November issue, due on newsstands this Friday, will be its last.