Joseph Carmoney is sentenced to nine years in prison for a robbery in the 36-hundred block of Glenwood in January.
Police say when he was arrested for a another robbery, they questioned him about the robbery in his grandparents home.
They say he admitted he and two accomplices went into a window and robbed his grandmother with a gun.
The victims told police Carmoney had stolen from them in the past to support a drug habit.
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