It happened Monday evening outside a supermarket.
Heather Elliott spotted a 4-year-old boy and his 1-year-old brother inside a car with the windows rolled up. Elliott says the 4-year-old was crying hysterically.
Police later measured the heat index at 97 degrees.
As Elliott approached the children's mother, she allegedly began hitting Elliott.
Twenty-one-year-old Heather Query is charged with neglect of a dependent and battery.
The children were released to their father.
ABC7News: Mom left kids in hot car, beat woman