Northvale Police Sgt. Michael Graham did CPR on the unconscious youngster and "saved the boy's life," , borough Police Chief Michael Mazzeo told Daily Voice.
It was around 4 p.m. Sunday when another child told the adults at the Colonial Road gathering that "something was wrong in the pool," the chief said.
Guest Thomas Mulhern, 39, "jumped in and pulled the unconscious boy out," then handled him off to his wife, Danielle Bolger Mulhern, a witness at the party told Daily Voice.
Graham, who lives in Emerson, then began CPR, the witness said.
The boy regained consciousness and "eventually began talking" as emergency responders arrived and took over.
He was taken to Hackensack University Medical Center, the police chief said.
The witness reported Monday that the boy was "safe and well."
Boyd A. Loving contributed to this story.
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