No bond was set for a south Fulton County mother facing a child cruelty charge after police said she left her 3-year-old son in a locked car for three hours.

Lillian Stone, 25, waived her first appearance hearing Wednesday, according to Channel 2 Action News.

Stone was questioned for nearly seven hours and taken to the county jail late Tuesday, the news station reported.

One of Stone’s family members told Channel 2 on Wednesday: “She’s a great mother, and this is a mistake.”

About 3:30 p.m. Tuesday, Fulton police got a call about a child in a car in the 6800 block of Smoke Ridge Drive in the city of South Fulton, Cpl. Maureen Smith said. He had been found by a concerned citizen, who called 911.

The child was taken to Children’s Healthcare of Atlanta at Hughes Spalding, where he is listed in critical condition. It is unclear if he will survive, authorities told Channel 2 Action News.

Stone is due back in court Nov. 15.

Details on what exactly happened have not been released, but the child’s injuries were heat-related, Smith said.

The high was 72 degrees in Atlanta Tuesday, according to Channel 2. It was not clear how hot it was inside the vehicle.

However, recent studies have found the temperature inside a closed vehicle can reach dangerous — and potentially fatal — levels for children in a short amount of time on mild weather days.

Testing by Consumer Reports showed that even when it was 61 degrees outside, the temperature inside a closed car reached more than 105 degrees in just one hour.

“Temperatures that might seem comfortable for adults can quickly become dangerous for children,” Consumer Reports medical director Dr. Orly Avitzur said.

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