Mom Pleads Guilty to Killing Daughter Who Had Cerebral Palsy: 'I Don't Want Her to Live in An Institution'

Chicago mom pleads guilty to manslaughter in botched murder-suicide of her disabled daughter.

A suburban Chicago mother has pleaded guilty to killing her disabled adult daughter with an overdose of pills in a botched murder-suicide plan.

Bonni Liltz, 56, was initially charged with first-degree murder in the death of her 28-year-old daughter, Courtney, who suffered from cerebral palsy and required round-the-clock care.

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In a plea deal, Liltz pleaded guilty Tuesday to involuntary manslaughter. She faces up to 14 years behind bars. Her attorneys, family and friends asked the court for leniency, citing the woman’s poor health.

She acknowledged putting an overdose of prescription medicine in her daughter’s feeding tube. The mother also took pills, washing them down with a glass of wine. She told authorities she had been battling cancer and was sure she would soon die.

She did not want to leave her daughter behind to be placed in an institution, she said.

Liltz recovered from the overdose, but Courtney did not.

Several people testified Tuesday on Liltz’s behalf, calling her a selfless, loving mother who “devoted her life to caring for her daughter,” according to lifelong friend Gloria Cheever.

Liltz adopted the girl at age 5, after Courtney’s birth mother and her adoptive parents surrendered custody of her, friends said.

She fed, bathed and cared for Courtney on her own, according to Tuesday’s testimony.

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Liltz’s mother, Gladys, said Tuesday that her daughter battled ovarian cancer at age 19, only to have a recurrence in 2012.

The second bout forced her to place Courtney in an assisted living facility while she underwent inpatient treatment, Gladys said. Courtney was not well cared for there, and was upset at being left at the facility.

“Bonnie has not had an easy adult life,” her mother said. “She has had many disappointments and yet she continued to provide the best life she could for her and her daughter,” Gladys said.

Liltz was expected to be sentenced Wednesday afternoon.

Watch: Mom Killed Son With Down Syndrome By Adding Hand Sanitizer to His Feeding Tube