Police say Miguel Ramos fell to his death in the Mount Hope section on Mount Hope Place just after 4 p.m. Sunday.
Investigators believe the boy climbed up on the air conditioner, somehow wiggled out the window, and fell to his death from the apartment.
Neighbors tell Eyewitness News that police responded quickly, started CPR then raced the boy to the hospital.
"Everybody was screaming. I felt the heart of everybody. Everyone here was screaming," said Geraldo Montes.
Leonor Castillo used to babysit the child and said he needed constant supervision.
"I knew him five days after he was born. He was a sweetheart. This gives me a lot of pain. We would go shopping. We never left him alone," Castillo said.
A close relative tells Eyewitness News the child had autism, was non-verbal, and was adopted - and that his adoptive mother embraced how special he was. She loved having to understand his every need without him uttering a word.
The mother also cared for other foster children in her Bronx apartment as well.
"The mother was in bad shape, but we have to wait to see what God does - everyone is united with her," Montes said.
"She was a real good mother. She really cared about him. Excellent mother," added Castillo.
Many neighbors commended the mother for her care and describe how she brought the nine-year-old to school every morning.
There are still many lingering questions as to how the fall could have happened.
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