Etowah County Judge Allen Millican convicted Sophia Rosienell Adams of aggravated child abuse involving a 22-month-old child.
Investigations began in 2008.
Medical examinations showed the child had been subject to burns from an iron being held against his hand.
Authorities say other signs of mistreatment included scars on the child's face, chin, shoulder and left hand.
Adams faces up to 20 years in the state penitentiary.
Sentencing is set for May 28.
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