Hanna Fernando, 40, died after a truck rear-ended her car and caused both vehicles to roll over.
Fernando's sister, Nicole Roberts, said she dropped to her knees when she got the phone call telling her Fernando was dead.
"I don't know how to go on without my sister in my life. She's always been a constant factor, and I'm angry. I'm so angry, and hurt and devastated," Roberts said.
Fernando was from south suburban Markham. She was raising four children, and one of them was her grandchild.
The driver of the truck was cited for failing to reduce speed to avoid an accident and for operating an uninsured vehicle, according to Illinois State Police. The truck driver was transported to an area hospital for treatment of minor injuries.