Neighbor Don Strong and his stepson rescued two children before firefighters arrived.
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“The house was on fire, and I was like, ‘Man, no one in there is going to be able to make it out alive,'” Strong said.
Neighbors said 35-year-old Yolanda Robinson died after she went back into the home to go after the three other children.
Firefighters were able to rescue the children and the man but said Robinson didn’t survive.
"They did a good job,” Strong said. “They walked in there and pulled everybody out."
Personal items remain scattered around the yard on Sunday, while ash covers the doorstep and part of the roof is completely gone.
"The fire was real bad,” Strong said. "I can't get it out of my head, because I was standing right there looking at the whole thing."
The other six victims were taken to area hospitals, police said.
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The man and other three children are being treated at the burn center in Augusta, Georgia.
"Five boys, young boys, to lose their mother like that is a hard thing,” Strong said.
The Rock Hill Police Department and the South Carolina Law Enforcement Division are conducting an investigation.
— No other information was released. Visit WSOCTV.com for the latest on this developing story.