Court papers filed in the case say Christina D. Carlson, 36, left Chantel Craig and a 2-year-old daughter alone on Oct. 8 in the car in which they were living. The younger daughter later was pronounced dead, and the 2-year-old required hospitalization.
Christina Carlson initially was charged in Tulalip Tribal Court, but the charges were transferred Thursday to U.S. District Court in Seattle on Thursday. In addition to murder, Carlson also faces two counts of criminal mistreatment.
On Friday a U.S. magistrate judge ordered Carlson held in federal detention. If convicted, she could face a maximum sentence of life in prison.
An autopsy showed Carlson's daughter Chantel suffered from dehydration and severe malnutrition, weighing just 18 pounds with prominent ribs and a sunken abdomen. She was found covered in urine and feces, with maggots in her diaper and lice in her hair.
Her older sister was found in a similar condition - pale but still alive - strapped into a car seat with abrasions on her skin and bleeding wounds. Her blanket was found to be infested with maggot larva and bed bugs.
Officers responded to the scene after receiving a 911 call from another woman who lives nearby. When they arrived, they found Christina Carlson performing CPR on her younger daughter, who was lying on the ground in front of the car.
An investigation found that neither daughter's diaper had been changed for days, and that the little girls had been mostly confined to the car - much of the time in warm weather with the windows rolled up, according to court documents.
Carlson told investigators that she had run out of diapers, but officers found a full package of unused diapers in the trunk of the car.
Witnesses also told investigators that Carlson and her daughters had been living in her car, that she never fed the girls anything but 2 percent milk, and that she smoked opiates in her car while her daughters were there, court documents say.
At the time of Chantel's death, state and tribal welfare workers had been trying to find Carlson for months after receiving reports that she had been severely mistreating and neglecting her daughters.