Updated

Eighteen years after her 8-month-old baby died, a mother walked into a police station and told officers she killed her son while staying at a home for unwed mothers, police said.

Elaine Teresa Patterson, 43, was charged with murder Tuesday.

"She just decided she had enough," said Greenville Police spokesman Lt. Mike Gambrell.

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The baby, Bill Rhinehart III, was born premature and spent five months in hospitals before coming home. Patterson was not married and left with her son after her mother told her she should go to a home for unwed mothers in Greenville, Gambrell said.

Not long after she arrived, Patterson told police she held her son against her breast until he stopped breathing, Gambrell said.

Patterson then called 911 and told paramedics she woke up and found her son unconscious, police said. He died in the hospital three days later on May 26, 1988.

An autopsy determined the child died from the rupture of a blood vessel outside the brain. But what caused that vessel to break was never determined, Gambrell said.

Three months ago, Patterson came into the Beaufort Police Department and told officers she wanted to turn herself in for killing her son.

Investigators sent Patterson's statement and the autopsy findings to a pathologist, who determined the injuries on the boy were consistent with being smothered, Gambrell said. Patterson was arrested at her home in Beaufort on Tuesday and remains at the county jail.

There was no phone number listed either for Patterson or her address.