NEW YORK (CBS 2) — A sickening discovery was made in Brooklyn Thursday, as authorities found a four-year-old girl – weighing only 15 pounds – dead, apparently having been tied to a crib.

Neighbors were shocked, not just to hear the young girl was dead, but also that the girl’s mother, 30-year-old Carlotta Pierce, was being questioned by police.

“It’s hard to imagine that anything criminal happened,” one neighbor said. “From what I’ve seen, she couldn’t have been a better mother.”

When paramedics got to the apartment, it was already too late – they pronounced the girl dead at the scene. However, they saw some things that disturbed them.

Responders told police that they saw marks on the girl’s wrist, and twine that seemed to have been tied to her. It wasn’t tied when they found her, but it seemed to the paramedics that the twine may have been keeping the girl in place.

It was the mother who called 911. Her daughter, four-year-old Marchella, was born with underdeveloped lungs, and she was extremely fragile.

The same neighbor who said she was a good mother also said he believed that, should she be found responsible, she should be punished.

“If [police find] something was wrong there, she must be held accountable,” he said.

Detectives questioned Pierce all day Thursday, trying to determine whether what happened was a tragic accident or criminal negligence.

The final answers may not be forthcoming until the autopsy, scheduled to be performed on Friday.

Witnesses say the little girl was so small that the medical examiner’s assistant carried her across his arms to the mortuary van.

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