CHICAGO (AP)– An Illinois father and stepmother will spend decades in prison in the starvation death of their 6-year-old son, who authorities say weighed just 17 pounds when he died.

FILE – This undated photo provided by the Jersey County States Attorney in Jerseyville, Ill shows Michael L. Roberts. The Illinois father and stepmother face sentencing after pleading guilty to murder in the starvation death of their 6-year-old son, who authorities said weighed just 17 pounds when he died. Roberts and Georgena L. Roberts of Jerseyville face between 20 and 60 years in prison. (Jersey County States Attorney via AP, File)

The Alton Telegraph reports a judge on Wednesday sentenced Michael L. Roberts to 25 years in prison and Georgena L. Roberts to 20 years.

The 43-year-olds from Jerseyville both pleaded guilty to first-degree murder in November. Two counts of endangering the life and health of a child were dropped.

Authorities have said the couple starved the boy as a form of punishment and withheld food and nourishment on a regular basis. When he died, the boy weighed about a third of the typical weight of a 6-year-old. A preliminary autopsy indicated he died of extreme malnourishment.

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