Saturday, Feb. 9—Rachel and Joshua Carson of Belmont, a daughter, Olivia Marie Carson, 7 pounds 6 ounces, 20 inches long, born at 3:38 a.m. at Mercy Medical Center. Grandparents are Martin and Janet Russell of Belmont, Scott and Diane Carson of Fort Atkinson, and Carol Carson of Charleston, S.C.  Great-grandparents are Don and Cecelia of Platteville and great-great-grandmother Wilma Russell of Potosi.