When her vehicle came out of the curve, Stefanko drove into the opposite lane and struck the pickup truck driven by Julie A. Johnson, 38, of Berkeley Springs, W.Va., McFarland said.
Johnson was in fair condition Tuesday afternoon with multiple injuries at City Hospital, according to police and a hospital spokeswoman.
Johnson's daughters, 1-year-old Sierra Johnson and 6-year-old Faith A. Mosher, were riding in the truck, McFarland said.
Faith A. Mosher was in fair condition Tuesday afternoon in the critical care unit at City Hospital and Sierra Johnson was treated at City Hospital and released, the spokeswoman said.
Witnesses said Stefanko, the only occupant in the Buick, had been swerving as she drove along W.Va. 9 toward Baxter Road, McFarland said.
Stefanko lived on Cherry Run Road with her mother, Christine Stefanko, and her grandparents, her mother said.
Christine Stefanko said her daughter was on her way home to get ready for school when the accident occurred.
Hedgesville High School Principal Don Dellinger said he informed students at the school about April Stefanko's death Tuesday. He said a crisis intervention team will be set up at the school today to help them deal with the loss.
Stefanko was a well-known student who took challenging courses and was enrolled in a nursing program at James Rumsey Technical Institute, Dellinger said. The nursing program is for students who might be interested in pursuing a nursing degree, Dellinger.
"She was a very nice, sweet girl," Dellinger said.