Fayetteville police said Norelly Lockamy, 21, had just picked up her three young daughters from a babysitter when the Chevrolet van she was driving rear-ended a Freightliner cargo truck traveling north on Bragg Boulevard around 5 a.m.
Investigators say Lockamy had a revoked drivers license.
One of Lockamy's 4-year-old twin daughters, Julissa Robertson, was thrown from the vehicle and killed instantly. Her twin, Capryana, suffered massive head injuries. Capryana is in critical condition at UNC Hospitals in Chapel Hill.
Lockamy and her 9-month-old daughter, Evona, were not injured. They were transported to Cape Fear Valley Medical Center as a precaution and released.
According to police, the 9-month-old was the only child restrained in a car seat.
Police are investigating whether Lockamy had been drinking and said some sort of charges are pending.
"What's relevant is what the traffic reconstruction may find and what the toxicology will tell them," said Sgt. Alex Thompson of the Fayetteville Police Department.
Police are also trying to determine if other factors contributed to the crash. They say when Lockamy drove over a rise in the road, there was thick fog in the area. Also, the truck she hit was only going 10 miles per hour because the driver was looking for an address.
The driver of the cargo truck, Roberto Espinosa, of Hialeah, Fla., was not injured in the collision.
No matter what the cause, police say serious charges are pending -- something like misdemeanor death by vehicle, upwards to murder.
The day before the crash, Lockamy was arrested for failing to appear in court. She was released on bond late Saturday afternoon.
Police say she went to work as a dancer at a strip club and then did some shopping before picking up her children at a sitter's house early Sunday morning.
Investigators say it could be two weeks before the tests are back on whether Lockamy was drinking.