Fire Department spokesman Mark Brady says 13-year-old Kelli Hernandez died Monday in Shock Trauma in Baltimore, where she was taken after the Jan. 19 blaze.
Kelli's sister, 9-year-old Kimberly Hernandez died at Children's Hospital the day of the fire.
Two other sisters were hurt in the blaze, which fire official believe was accidental. The fire caused $350,000 in damage.
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