11-year-old Andromeda Brown's body was found inside the trailer after firefighters extinguished the flames.
Fire Marshal's investigators say a 56-year-old woman was critically burned, and is now being treated at Pennsylvania's Crozer-Chester Burn Center, and a 2-year-old girl is in stable condition there.
A 14-year-old boy was released from Kent General Hospital after being treated for burns and scratches.
Investigators are still working to determine how the fire started, and are asking anyone who may have information to call them.
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