Police say 46-year-old Patricia Salegna-Maqueda died Tuesday night at Stony Brook University Medical Center.
Police say she was a representative from State Farm Insurance who was at the Brentwood home regarding a flooding claim when the explosion occurred last Tuesday.
The entire structure in the middle class neighborhood on Long Island was reduced to small shards of wood, plywood, drywall, insulation and other materials.
The dead toddler's parents were among four other residents who were injured. A plumber, seven police officers, two firefighters and two neighbors also were hurt.
Officials are still trying to determine what ignited the gas.
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