Firefighters were called to the smoke-filled corner home in the 900 block of Muhlenberg Street just after 9:45 a.m., officials said.
Crews rescued multiple people from the home, including 32-year-old Catherine May Dingle and her 9-year-old son, according to Berks and Lehigh County Coroner's Offices.
Dingle died of a combination of second-and third-degree burns over 86 percent of her body and smoke inhalation injuries Thursday night at Lehigh Valley Hospital-Cedar Crest, the Lehigh County coroner said. Her death was ruled an accident.
The boy, -- whose name has not been made public -- died at Reading Hospital just after 11 a.m. earlier that morning, the Berks County Coroner's Office told WFMZ.
Two children were being treated at area hospitals, the Berks County coroner's office told the outlet. The extent of their injuries is unknown.
A GoFundMe campaign in the homeowners' names had raised nearly $9,000 as of Friday morning.
"I am trying to raise money for my friend and co-worker Aaron (Ace) Torres, his girlfriend, Catherine May, and their children. They lost everything in a fire this morning. Several of the family members are in the hospital due to the fire and sadly his son passed away from the fire," GoFundMe organizer Jessica Smith wrote.
"All monies raised will go to helping them to regain housing, purchase necessities, medical bills they will have due to hospitalization, and funeral costs. Any donations will be greatly appreciated and I would like to thank you in advance for your support."
Reading Mayor Eddie Moran also encouraged the local community to keep the family in their prayers.
"I am asking everyone to please keep this family and the First Responders in your prayers and thoughts as they navigate this emergency," Moran wrote on Facebook.
"We all appreciate it."
The cause of the fire is under investigation by the local Fire Marshal's Office.
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