Linda Ann Howland, David Wayne Jones, and their 3-month-old daughter Leah Michelle Jones died when their home caught fire on April 26, 1998, according to PSP.
The family lived in a converted barn on a property that Howland ran as a horse farm, authorities said. A 1998 report from the Allentown Morning Call said the 42-year-old mom was "known as a key breeder and trainer of the Tennessee walking horse."
Howland's daughter from a previous marriage was also at the home but was able to escape, according to the Morning Call report.
Anyone with information is asked to call PSP Troop M at 610-861-2026 or submit a tip online.
Click here to read the Morning Call's 1998 coverage.
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