Fire crews initially rescued two people from a burning home in Pottstown in the area of East 5th Street around 2:30 a.m, according to Pottstown fire chief Frank Hand.
Joseph Norton, 48, was pronounced dead at Pottstown Hospital from smoke and soot inhalation, officials with the Montgomery County coroner's office told 6abc.
His 12-year-old son, Tyler Norton, was also killed, officials said.
Norton's wife and the boy's mother, 47-year-old Bernadette Norton was pronounced dead at Lehigh Valley Hospital-Cedar Crest Monday evening after initially being listed in critical condition, according to the Lehigh County coroner's office.
An autopsy will be performed on Wednesday, June 23, to determine the cause of death.
A firefighter was also injured due to heat exhaustion but is expected to have a full recovery.
There was no immediate word on how the fire started. It is under investigation by the Pottstown Police Department.
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