CHICAGO (CBS) — A Schaumburg woman convicted of killing her severely disabled adult daughter and set to return to prison has apparently committed suicide.

Bonnie Liltz pleaded guilty in 2016 to involuntary manslaughter in the death of her daughter.

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Liltz had cancer and claimed she feared for her daughter’s future as her own health declined.

Schaumburg Police Sgt. Christy Lindhurst says a 911 call came from a family member and officers went to Liltz’s apartment.

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“At that time a death investigation started and the Cook County Medical Examiner responded to the location,” says Lindhurst. “At this time we have no evidence of any foul play and we believe to be a suicide.”

Lilltz wound up appealing her case and was free on bond, but the Illinois Supreme Court declined to hear the appeal.

A lower court judge ordered Liltz to return to prison.

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