A Montgomery County jury convicted Daphne Spurlock on Thursday of injury to a child.
The child's father returned home in March 2012 to find him covered in blood. The boy spent a month in a hospital and then underwent many months of rehabilitation.
Spurlock, 45 at the time, told investigators she was reading the Bible with her son and realized he was possessed. She stomped on his chest and face and then cut him with a kitchen knife.
Prosecutor Tyler Dunman says Spurlock used an insanity defense but couldn't convince the jury that she didn't know her actions were wrong.