Paul Fronczak learned two months ago from DNA tests that he is not the biological son of the couple who raised him, ABC News reports. The FBI located him in New Jersey in 1965, and investigators believed he was the baby a woman posing as a nurse took from Dora Fronczak the year before at Michael Reese Hospital.
Fronczak, interviewed for ABC's 20/20, said he is trying to help his parents.
"I would want nothing more than to have them be able to meet or at least know what happened to their real child before they're gone," Fronczak said.
Chester and Dora Fronczak still live in Chicago while Paul lives in Nevada. ABC commissioned Phojoe, a Michigan company, to determine what the couple's biological son might look like at the age of 49.
Artists used a photograph taken when the baby was a day old and the appearance of Chester Fronczak and a younger son, David.
"It's tough working from just a baby photo taken at one day old, but I think this is pretty close," said Jovey Hayes, the artist who worked on the image.
The investigation into the kidnapping was closed years ago, but the FBI has now reopened it.
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