Two North Idaho women were traveling south on highway 95, near Plummer, Idaho, when the driver hit a moose.
The crash happened Wednesday, just after 7:30 p.m.
According to Idaho State Police, the 2002 Mitsubishi Galant was driven by Andrea George, 20, of Desment, Idaho.
Sophia George was riding as a passenger.
Andrea was wearing a seat belt, but Sophia was not. Andrea was taken to Kootenai Medical Center. Sophia was transported to Sacred Heart Medical Center. As of 4 a.m. Thursday, Sophia was in critical condition.
Coeur d'Alene Tribal Police assisted ISP with the investigation.