Reid Naizer, who went into cardiac arrest about 3 p.m. last Tuesday, while he was at his home on 156th Street, near 107th Avenue, died of natural causes, according to the NYPD.
The boy was taken to Jamaica Hospital where he was pronounced dead on arrival.
Police said that there were bruises on the boy's body but after an investigation they said they found nothing suspicious.
Medical Examiner office spokeswoman Julie Bolcer said that the specific cause of death "is pending further studies."
Police said that the baby was born prematurely.
Neighbors, who described the family as "very tight-knit," said that the boy had heart problems and was often hospitalized.