Juan Carlos Pedilla, the 28-year-old father of two, was killed. Police said the driver of the car he was riding in ran away.
"I still don't understand how if he was a close friend that he would just leave him there," said Kimberly Trujillo, Pedilla's cousin.
Two teenage girls who were in the same car were critically injured.
"We understand the students are making progress. Both are strong girls and resilient. We are very happy that they're improving," said Diana Smith, principal of York High School in Elmhurst which the girls attend.
It is not clear how the girls, 15- and 18- years old, ended up in the car with Pedilla and the driver. State police said the white Infinity FX Crossover was likely speeding in the southbound lanes early Tuesday morning when the driver lost control, slammed into the center divider and rolled over into the northbound lanes. Pedilla, who was in the front seat, was thrown from the vehicle. The 30-year-old driver, who initially ran from the scene, has since turned himself in. But he has not been charged.
Pedilla's relatives will accompany his body back to his native Mexico.
"He wanted to go to Mexico to baptize his daughter. He wanted to see his mother, who he hadn't seen in four years, so he was going to introduce his daughter and his girlfriend to his mom," said Trujillo.
Pedilla was not wearing a seatbelt, and his cousin hopes his death will remind people to buckle up. Trujillo believes that if he'd been wearing it he might be alive.
Pedilla leaves behind two daughters, an 8-year old and an 11-month old.