Jason Reish's lifeless body was found in the family's apartment in Mamaroneck, and police are still trying to figure out exactly what led to the horror they found inside the Continental View Condos.
On Monday night, police removed evidence bags from the complex just hours after making the disturbing discovery.
Officers responding to a request to check on 46-year-old Manuela Maria Morgado found her semi-conscious inside her home and little Jason dead.
They say she tried to kill her son by using a mask attached to a helium tank. She apparently then tried to kill herself - by taking pills.
Neighbors, including a woman who taught Jason in a nearby child development class, are still stunned by the news.
"He was a good kid, he was sweet and very energetic," she said. "I broke down. I broke down. It was shocking."
Reports say Morgado and Jason's father are divorced and in a custody battle.
"She just seemed to be a terrific, very upbeat person," neighbor Andrew Landau said. "Always with the son. The dozen conversations I had with her were absolutely terrific. Nothing that would give you any sense that something like this would happen."
Morgado is now charged with second-degree murder.
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