The Lehigh County coroner's office says 34-year-old Robyn Foose died from her injuries Wednesday at a hospital in Allentown.
A caregiver at the Mechanicsburg group home where Foose lived discovered her with her clothing ablaze on Friday evening. Police say Foose appears to have accidentally started the fire while playing alone with a child's magnifying glass.
Police said Foose had suffered second- and third-degree burns over half her body.
A spokeswoman for the Keystone Human Services group home has said the fire was an accident.