The Allegheny County Medical Examiner's office announced its finding Wednesday. The agency says Roland Williams died from a blunt impact injury to his head.
Authorities say the toddler fell from the window of a third-floor apartment in Sharpsburg shortly after 7 p.m. Saturday. He was taken to a hospital but died there Sunday night.
No other injuries were reported in the incident.
The death remains under investigation by county police, who say it is not considered suspicious.
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