The car came to a stop on the side of the road and the girl rushed out of the car where she was assisted by other passing motorists.
She told witness that her mother had begun having breathing problems and pleaded with the girl to shoot her. The daughter refused, so the mother pulled the trigger herself.
Family members said the woman, a medic in the Army Reserves, and her daughter were on their way Oklahoma to visit relatives, the Las Cruces Sun News reported.
-- Lance Murray