Thirteen-year-old Julian Amador died after a Sanger ISD school bus overturned in Denton County on September 24. He was one of four students aboard.

The Texas Department of Public Safety said the bus was heading north on Huling Road just before 5 p.m. when it left the roadway, hit a culvert and rolled over. What caused it to leave the road remains unclear.

Julian’s parents, Brenda Lopez and Emmanuel Amador, say they are grieving and want to know what happened before the crash. Amador was waiting at Julian’s bus stop when he got a call about the incident and drove to the scene.

The driver has been identified as 38-year-old Jesse Padgett. The district has not said whether he remains employed.