Officers were called to the Chickie's and Pete's restaurant around 1:30 a.m. Saturday.
When they got there, they found bystanders had already removed Brandon Morgan's 3-year-old from the car.
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Investigators say the toddler had been left in the vehicle, which was not running for three hours.
Despite the 85 degree heat, the boy was okay and was released to his mother.
Morgan is now facing a number of charges, including child endangerment.
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