MENDHAM TOWNSHIP, New Jersey (WABC) -- Investigators announced Thursday they have solved the case of an infant found dead nearly 40 years ago in Mendham Township, New Jersey.
The body of the newborn, named Baby Mary after she was found, was discovered in a plastic bag and wrapped in a towel inside the Dismal Harmony Natural Area by a couple of boys who were fishing nearby on Christmas Eve of 1984.
The baby was found with the umbilical cord still attached.
Police in Mendham took this case to heart and never gave up their search for the killer.
WATCH: Update on unsolved 1984 'Baby Mary' case
It led them to the baby's mother after a long investigation, which went from Morris County to Florida and eventually South Carolina, where the mother was taken into custody.
She is now 57 years old but was just 17 at the time of the crime. She and the father lived in Morris County back in 1984.
The father of the child died, and investigators determined he did not know anything about the crime.
This case took a lot of police work to solve, but modern-day technology played an important role in finding the person police say is responsible for dumping Baby Mary.
"DNA of the baby was taken, obviously, at the time of the discovery," said Morris County Prosecutor Robert Carroll. "DNA analysis led investigators to an identification of the father. Thereafter, literally running down hundreds, if not thousands, of leads led to identification of the mother. Both the father and the mother have been verified through DNA as being the proper mother and father."
The mother is being charged with manslaughter.
She is being charged as a juvenile since she was a teenager at the time of the baby's death - and for the same reason, her name was not released by prosecutors.
If found guilty, she could face up to three years behind bars.
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