By Steve Tawa

PHILADELPHIA (CBS) — The mother of an infant who died in Fort Worth, Texas 45-years ago says they were “surprised and suspicious” that someone had assumed his name for more than 20 years. A 44-year old Lansdale man now faces federal identity theft and Social Security fraud charges.

Peggy Laskoski says while her sister recently did a routine search to put their family tree together, a “green leaf” appeared for her deceased son, Nathan. After clicking further, they found his name was linked to marriages and residences in several states.

“The dates showed that he was about the same age our son would be,” Laskoski said. “Our main emotion was extreme alarm.”

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She recalls getting a “strange” telephone call in 1996, from a man asking her questions about Nathan, including his Social Security number, but when she pressed him, the caller hung up.

“Nathan never had a Social Security number,” Laskoski said. “No one thought identity theft was an option, because people are obviously after Social Security numbers.”

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She contacted police, who considered it a scam.

Federal prosecutors now believe that shortly after Jon Vincent escaped from a Texas halfway house in 1996, he stole the name of the boy and crafted a new identity. Investigators allege he fraudulently obtained a birth certificate for the true Laskoski, which he used to apply for a Social Security number in Laskoski’s name.

Peggy Laskoski says it was a “monstrous and heart-wrenching crime,” but she commends investigators for their swift and thorough followup.