The baby was flown to the burn unit at Akron Children's Hospital following the late Friday night accident.
A spokeswoman at Akron Children's Hospital confirmed the hospital was treating the baby Monday, but said her condition wasn't immediately available.
The child's grandmother, Carol McCormick, injured her fingers rescuing the baby. She told WFMJ-TV in Youngstown the child's entire face is burned.
"All I could do was just react," McCormick said. "I didn't think. I reacted. I grabbed hold of the firework and then the bed caught on fire that she was laying in."
The child sustained first-, second- and third-degree burns on her face and hand, McCormick said.
Police are investigating.
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