A female motorist ran a red light while traveling east on Garfield Boulevard and struck another car, according to Kubiak, who said the woman was driving her 2-year-old son to University of Chicago Comer Children's Hospital at the time of the crash.
The Cook County Medical Examiner's office confirmed the toddler's death but said the boy's death was natural. He was suffering from leukemia and was in hospice care at the time of the crash. He did not suffer trauma from the crash, a spokesman said.
The police Major Accidents Investigation Unit is investigating the crash.