SCHAUMBURG — Authorities say a suburban Chicago mother who was scheduled to return to prison for killing her severely disabled daughter in 2015 has been found dead of an apparent suicide.

The Cook County medical examiner’s office says Bonnie Liltz was pronounced dead Saturday. The 57-year-old was to return to prison Monday.

Schaumburg Police Sgt. Christy Lindhurst says authorities haven’t found any evidence of foul play and believe it’s a suicide.

Liltz was sentenced in 2016 after pleading guilty to involuntary manslaughter in the death of her adult daughter. Liltz has had cancer and said she feared for her daughter’s future as her own health declined.

Liltz was released on bond while she appealed to the Illinois Supreme Court, which declined to hear the case. A county judge ordered her to report back to prison.