A man charged with killing his ex-girlfriend and her father in southwestern Michigan in 2016 has agreed to be sentenced to 40 to 60 years in prison in a plea deal.

The Herald-Palladium of St. Joseph reports 26-year-old Alex Perez will be given his punishment July 16 after pleading no contest but mentally ill to two counts of second-degree murder. He was charged in the deaths of 27-year-old Renee Mitchell and her father, 67-year-old John Mitchell, near Coloma.

Stephanie Kopaceski, whose sister and father were killed, says the expected sentence "isn't enough." She says: "It should be life for a life."

Perez and Renee Mitchell had two daughters. Police found Perez and the girls in Georgetown, Colorado, after an Amber Alert. Police believe Perez was returning home to Los Angeles.

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