Forty years after she left her newborn to die in a wooded New Jersey area on Christmas Eve, Mary Catherine Snyder Crumlich was living a suburban life in South Carolina with her husband and sons, social media shows. 

But earlier this month, 57-year-old Crumlich was sentenced to a year behind bars for manslaughter in the death of the infant Mendham Township Police called “Baby Mary” during their decades-long investigation, the Morris County Prosecutor’s Office announced. 

Mendham Township Police Chief Ross Johnson told Fox News Digital a DNA profile was established for the baby girl in 2014 and “a lot of great police work” solved the decades-old cold case.

Crumlich was just 17 when she left the child, her umbilical cord still intact, wrapped inside a towel in a plastic bag, which two young boys playing in a stream found and reported to police, the prosecutor’s office said. The death was ruled a homicide after a coroner determined the child had died before she was placed in the bag, police said. 

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The baby girl’s identity was not known, but the Rev. Michael Drury at St. Joseph Church baptized her, Johnson told Fox News Digital. Each year on Christmas Eve, Johnson said, officers would visit the grave for a memorial service. 

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“It became part of our yearly tradition. We didn’t want Baby Mary to be forgotten,” Johnson said on Friday. “[It was] such a horrible act, really senseless in every sense of the word. We wanted to make sure she was remembered every Christmas Eve. … It’s just completely unnecessary. Even in the ’80s, there were so many resources in our area. It didn’t need to go down that way for sure.”

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When a DNA profile was established for the child, her case was reopened by the Morris County Cold Case Unit. With the help of a genealogist, Johnson said, detectives looked for families living in the area who had daughters between 16 and 19 years old and whose racial and ethnic backgrounds matched the girl’s. 

“There was never a belief that it was just some random person from out of town,” Johnson said. “The spot was so specific, it would have to be someone from the area.”

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Detectives interviewed dozens of families and chased a litany of tips and theories. Finally, they found a match for Baby Mary’s DNA, an area man who had died by suicide years earlier, in 2009 or 2010, Johnson said. 

“It is our firm belief he had no knowledge of this. That’s why his name hasn’t been anywhere,” Johnson said. “We had no evidence that he had any idea that he was the father of that particular child, let alone that Crumlich was even pregnant.

“Maybe he wouldn’t have done that if he knew,” he added. “Maybe if he had a kid, if the kid didn’t die, the story would be different.”

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Through his family, they zeroed in on Crumlich, who had moved to suburban Columbia, South Carolina. 

On Facebook, she is pictured attending her son’s baseball games and weddings. Later, she posted photos babysitting her grandchildren. 

“I can’t imagine living with something like that. There are consequences.”

— Mendham Township Police Chief Ross Johnson

She was arrested April 23 last year and charged as a juvenile due to her age at the time of the offense. If she had been convicted as an adult, the prosecutor’s office said, it would have been on a second-degree manslaughter charge. 

Law enforcement was unable to refer to her by name until her conviction earlier this month, according to state laws for juvenile defendants. On April 3, Johnson said, Crumlich began a 364-day sentence at Morris County Correctional Facility. 

It was not immediately apparent who represented Crumlich in her case.

Johnson said he hopes Crumlich “finds closure on her end” after her prison sentence.

“I can’t imagine living with something like that. There are consequences,” he said. “It’s good to see that she carried on with her life, [but] she lives with this every day to some degree. I’m happy, even for her sake, that we could bring closure to this. The reality is that she left a newborn baby out in the woods. She did that, and we felt it was very important to bring that to justice.”

Johnson said he was “left with more questions than answers” even after the case was resolved.

“I really do hope one day when she gets out of jail she does come public with the whole story,” Johnson said. “But I don’t think that will ever happen.”