The Pasco County Sheriff's Office says its deputies tried to save Devin Vatter by performing CPR on him after being called to a house in New Port Richey, Florida on Monday.
The Tampa Bay Times reports the boy was taken to the hospital, where he died.
Authorities have not released the name of the grandfather, while the death continues under investigation. Sheriff's Office spokesman Kevin Doll said the paternal grandfather had been caring for the boy, whose father had died.
Information from: Tampa Bay Times (St. Petersburg, Fla.), http://www.tampabay.com.
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