CHICAGO -- An Illinois family remained in shock Thursday after a teenage girl died in a car accident while attempting to save her pet dog from being put down.

Taylor Mae Stinchcomb, 15, stole the family minivan and fled her home in Gurnee, Lake County at midnight Tuesday with her cancer-stricken Doberman, Romulus, and a friend, the Chicago Sun-Times reported.

When Taylor became too distressed to drive, the 15-year-old friend took over the wheel.

The unnamed friend later lost control of the van and crashed into several trees and a utility pole, police said.

Taylor was taken to the hospital where she died of multiple internal injuries. Her dog Romulus was thrown from the vehicle and also killed. The friend survived.

"This case is absolutely heartbreaking," Lake County Undersheriff Charles Fagan said. "Our thoughts and prayers go out to the families of both girls involved in this incident."

It is not clear where the girls were heading in the van or if they had a plan.

Taylor, who just completed her freshman year, is survived by her parents, two sisters and a brother.