The family of Alejandra Valeri Espinoza-Velasquez gathered Saturday at her Manassas area home to celebrate the 19-year-old’s graduation from trade school. Some family members came from as far away as New York City to celebrate the young woman’s success.

The festivities ended about 4 a.m. Sunday, according to an account given by Espinoza-Velasquez’s boyfriend, Leonardo Canales. Because Espinoza-Velasquez, who has studied to become a medical assistant, does not drink, she offered to drive a large group home to Woodbridge, Canales said. Nine people, including two children, crammed into a 2004 Ford Explorer.

The trip ended tragically. Before they reached their destination, Espinoza-Velasquez lost control and the Explorer ran off the road, rolling several times, Prince William County police said.

Doris Aucapina-Espinoza, 43, who Canales said was Espinoza-Velasquez’s aunt, was killed in the crash. Police said a 4-year-old boy who was not wearing a seat belt was badly injured. Other passengers, including a 6-year-old boy, have varying injuries, police said.

Espinoza-Velasquez faces four felony charges related to injuries to the children, as well as one count of reckless driving and one count of failure to secure a child in a safety seat. She has been released on a $10,000 secured bond, and a court date has been set for Dec. 6.

Police said in a statement that “speed, alcohol and drug use are not believed to be factors in the crash at this time.”

Canales said Espinoza-Velasquez told him that she was driving south on Dumfries Road when she spotted a driver behind her swerving in and out of her lane. She suspected he was drunk and became nervous, Canales said.

When the driver went to pass her on her left, she thought the Explorer might be hit, Canales said. He said she told him that she was swerving out of the way when the accident occurred.

Police declined to comment on the account Espinoza-Velasquez gave Canales.

The car’s passengers range in age from 4 to 49. Two men, a 49-year-old and 36-year-old, are from Lindenhurst, N.Y., and Brooklyn, N.Y., respectively.

The rest of the car’s occupants are from Woodbridge, including the 6-year-old, 4-year-old, a 17-year-old male, a 38-year-old woman and a 39-year-old man. The 17-year-old was treated at the scene and released, police said. The names of the passengers were not released.

Sunday was a particularly deadly day on Northern Virginia roads. Four people were killed within an hour in Loudoun County on that morning in two traffic crashes. Separately, four were killed in two wrecks in Fairfax County.