The incident occurred at about 2:15 p.m. in the first block of North Lockwood Avenue.
Police said the woman grabbed the child from a backyard where she was playing with other children.
The woman then took the child across the street to a store, police said.
The child's relative saw what was happening and was able to confront the woman and bring the child back home, police said.
Police are looking for the woman.
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