Police say the three-year-old was found unconscious and unresponsive at an apartment building on Longfellow Avenue in the Bronx. Her mother's boyfriend called 911, and Crystal was rushed to Bronx Lebanon Hospital where she died.
Eddie Nicholas says he witnessed a man screaming as EMT's took the girl away.
"'My daughter died, my daughter died!' I said 'what happened?' and he couldn't say," said Nicholas.
Crime scene investigators shuffled in and out of the building. They photographed the scene and interviewed witnesses, but they kept quiet about what they might have found or what they were looking for.
Police say they are questioning both the girl's mother and boyfriend as a part of the investigation.
"She was always with her stepfather, because her mother used to work," said Crystal's cousin, Pastora Perez.
In fact, Crystal's mother was working at a nearby bodega when she got the terrible call that her daughter had been taken to the hospital.
An autopsy on Saturday revealed no conclusive cause of death.
The medical examiner says the circumstances are undetermined pending police investigation.
So far no one has been charged.
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