Ryan, who was living with terminal lung cancer, checked into Riverside Medical Center in Kankakee last Friday. She was relying on a respirator to help her breathe, her husband's attorney and former Illinois Governor Jim Thompson said.
The family decided Monday night to take her off the respirator with everyone there. Ryan passed away peacefully with her family at her bedside, Thompson told NBC Chicago.
Thompson said the family will hold a private funeral soon and a memorial service when Ryan is released from prison.
Gov. Pat Quinn in a statement praised Ryan for her dedication to "those whose voices weren’t heard."
"She inspired many with her strength and grace throughout her fight against cancer," Quinn said. “Her passing is a loss to the people in Illinois.”