OSCEOLA COUNTY, Fla. -- A 14-year-old girl behind the wheel of a car is accused of causing a deadly accident in Osceola County, investigators said. Allison Sullivan was driving a car with four other people inside, including a 3-year-old.

"It alarms me that someone that young was driving," one witness told Eyewitness News.

For an unknown reason, the car left Absher Road Saturday night near St. Cloud, hit a curb, then flipped into a culvert.

The car went airborne, throwing 12-year-old Shauna O'Rourke and her 25-year-old brother Daniel O'Rourke out of the vehicle. The 12-year-old later died at a hospital.

“We want to find out why this 14-year-old girl was driving when, clearly by Florida law, she shouldn't have been behind the wheel," Florida Highway Patrol Sergeant Kim Miller said.

No one in the car had a driver's license, including the 25-year-old. State troopers said he had been caught twice in the past two years for driving with out a license.

Now, some are asking how the accident could have happened in the first place.

"Kids who don't know what they're doing have no business driving, let alone in conditions like this,” one witness said.

Troopers said three of the four children escaped with only minor injuries. Daniel O'Rourke was still in the hospital in serious condition Sunday.

Charges are pending against Sullivan, the 14-year old driver, and Daniel O'Rourke, who has a history of driving without a license.