CPD said an adult man in a home in the 100-block of North Latrobe was trying to holster his gun when it accidentally discharged.
The 3-year-old boy was struck in the shin. He was taken by ambulance to Stroger Hospital in good condition, Chicago police said.
No further details were immediately available. Police did not say if anyone was in custody or if charges were being pursued.
Area four detectives are investigating.
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