23-year-old Sophia Charles was not only arrested, but her 2-year-old child was taken out of her custody.
Newark police say Charles left the child locked in her car, on the 700 block of Broad Street, while she went shopping.
Katrell Thomas just happened to be walking by, and spotted the child.
"I saw him, he was slumped over," said Katrell Thomas, a witness.
He got help and police arrested Charles when she returned to her car.
"It's very irresponsible, someone could have harmed the child, could have gotten overheated and passed out," said Tameshia Holloway, a Newark resident.
University Hospital ER Dr. Hosseinali Shahidi says small kids are especially vulnerable to the heat of a locked car in sweltering temperatures.
"Their temperature goes up, they sweat if they can, everything becomes disturbed in their body system because they can't get rid of the heat," Dr. Shahidi said.
And in extreme cases, it could be, and has been often times, deadly.
"Heat stroke, dehydration, they could die. (How quickly could that happen?) Depending on the temperature, very quickly," Dr. Shahidi said.
The child was treated at University Hospital and is fine, and also very lucky someone stopped and noticed.