The Cobb County Medical Examiner could have some crucial answers this week in the case of a child accused of killing her own baby and then hiding the body.

The 13-year old Mableton girl has not been publicly identified because of her age. She faces charges of first degree murder, first degree child cruelty and concealing a death. Police said she gave birth just after midnight Tuesday in her bedroom as her parents lay sleeping in the room next door. After the baby was born, the young mother fell asleep. When she awoke hours later, the baby was dead, according to investigators. 

Wednesday afternoon, witnesses told police they saw the girl and some friends burying a shoebox with the baby's body inside in some woods behind the Sierra Forest Apartments on Mableton Parkway. The young mother was arrested Thursday night. Her parents and the baby's 14-year old father were not arrested.

"She's being treated as an adult for trial purposes, but as a juvenile for purposes of incarceration," said WSB legal expert Ron Carlson, professor emeritus of law at the University of Georgia. Carlson called this a sad and rare case. He said the girl's fate could well hinge on what the medical examiner determines about the death of the baby. 

"Probably the most important element may be the question of whether there was a live human being here," Carlson said.

If the medical examiner finds the baby was stillborn, Carlson said the case against the 13-year old mother probably will not stand as filed. But if the baby was born alive and died later, that could mean the state will go ahead with murder charges.