Police said the shooting happened inside an apartment in the Woodlawn neighborhood's 800-block of East 65th Street just after 4 p.m.
The child, a 3-year-old boy, was grazed in the arm.
The victim was transported to Comer Children's Hospital in good condition.
Police did not immediately provide information about what may have happened before the shooting.
No one is in custody and Area One detectives are investigating.
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