ABC7 also confirmed the child attended Greenwood Elementary and had been picked up by Happy Days daycare staff from school.
The weapon was inside the child's backpack, and when the child put the backpack down, the gun went off.
The Harvey Police Department said it has not taken disciplinary action against the officer yet since the investigation is ongoing.
A spokesperson for the village of South Holland said last week, "An investigation is underway related to an apparent unintentional discharge of a weapon at a facility located at 831 E. 162nd St., South Holland. Due to the involvement of a juvenile, further details cannot be released at this time."