Burgos was reportedly unconscious when they arrived at the hospital and he was soon pronounced dead, authorities said.
An autopsy was completed, which determined the boy had been strangled to death with a tablecloth.
When talking with police, McKinzie allegedly said she had been planning her son’s death for several days and ultimately strangled him when he was asleep in the backseat, WTVJ reported.
After his death, McKinzie allegedly ran errands around Miami-Dade County while her son’s body was still in the car, officials said.
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On Nov. 16, McKinzie was arrested and booked into the Miami-Dade County Corrections and Rehabilitation, authorities said.
She was charged with first-degree murder and is being held without bond.
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