"All she was yelling was, 'It fell on his head, it fell on his head,'" said Jennifer Schieferstein, a lifeguard.
Schieferstein heard the mother's frantic calls.
She ran across the parking lot at Ransom Beach until she could see the mother.
"She had the little boy draped over her shoulder and his head is sort of bleeding down her back and on her shirt," Schieferstein said, "I checked for a pulse, he had a pulse, we laid him on his side so he wouldn't choke on blood because he was coughing, he was still coughing."
Schieferstein says she and the mother used napkins to try to cover the gashes in his head.
Police say the entire thing was just a horrible accident and there's no criminality involved.
The supervisor of the Town of Oyster Bay says they're working with town employees to figure out why the fence was propped against the wall.
In a statement to Eyewitness News, Supervisor John Venditto said, "This is among my darkest hours as the Oyster Bay Town supervisor. I don't even have the words that can express how upsetting this incident has been."
Schieferstein says she can't stop thinking about the little boy and the three frightened little girls who were there with him.
"They kept asking, 'Is my brother going to die, is my brother going to die?'" Schieferstein said.
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