The toddler was in the 300-block of East 87th Street in Chatham about 1 p.m., when the gun went off, CPD said.
The boy was taken to Comer Children's Hospital in critical condition, police said. He later died, police said.
The Cook County Medical Examiner's Office later identified him as Kh'aden Johnson.
Chicago police said there has been a person of interest identified in connection with the shooting.
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It was not immediately clear how the child got the gun.
Area detectives are investigating.
This is a developing story; check back with ABC7 Chicago for updates.
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