Dora & Chester Fronczak

Dora and Chester Fronczak were the loving Chicago couple whose infant son, Paul Joseph Fronczak, was abducted from Michael Reese Hospital just one day after his birth on April 27, 1964. Fifteen months later, they joyfully welcomed home a toddler found abandoned in New Jersey, believing he was their missing son.

For nearly five decades, they raised him as Paul Fronczak, never knowing that DNA would eventually reveal he was not their biological child.

Paul Joseph Fronczak / Kevin Ray Baty

Born on April 26th, 1964, Paul Joseph Fronczak was abducted from Michael Reese Hospital in Chicago just one day after his birth, launching one of the nation's most publicized missing child investigations. For nearly fifty years, his fate remained unknown while another child—Jack Rosenthal—was mistakenly raised as Paul.

In 2019, advanced DNA testing finally revealed the truth: the real Paul Fronczak had been raised as Kevin Ray Baty in Manton, Michigan, unaware of his true identity. The discovery solved the mystery of the kidnapped Fronczak baby, but it also uncovered an even larger story—that the child raised as Paul was actually Jack Thomas Rosenthal, whose twin sister, Jill Lynn Rosenthal, disappeared in 1965 and has never been found.

Kevin passed away in 2020, just months after learning the truth about his identity.

Jack Thomas Rosenthal

For nearly fifty years, the world knew him as Paul Fronczak—the child believed to have been recovered after the 1964 kidnapping from Michael Reese Hospital in Chicago. In 2012, DNA testing revealed the unimaginable: he was not the missing Fronczak baby.

Further genetic genealogy uncovered his true identity as Jack Thomas Rosenthal, who had been born on October 27, 1963, in Atlantic City, New Jersey, alongside his twin sister, Jill Lynn Rosenthal. While Jack had unknowingly been raised by the Fronczak family, Jill vanished as a toddler in 1965 and has never been found.

Gilbert & Marie Rosenthal

Gilbert and Marie Rosenthal were the biological parents of twins Jack Thomas Rosenthal and Jill Lynn Rosenthal, born in Atlantic City, New Jersey, on October 27, 1963. Their family became the center of a mystery when Jill disappeared as a toddler in 1965 under circumstances that have never been fully explained.

For decades, their story remained hidden until DNA testing revealed that the man raised as Paul Fronczak was actually Jack Rosenthal, setting in motion an investigation that uncovered a second missing child, long-buried family secrets, and one of the most extraordinary identity mysteries in modern history.

Jill Lynn Rosenthal

Jill Lynn Rosenthal was born on October 27, 1963, in Atlantic City, New Jersey, alongside her twin brother, Jack Thomas Rosenthal. While Jack was unknowingly separated from his family and raised as Paul Fronczak, Jill disappeared in 1965 at just twenty-one months old under circumstances that remain unknown.

No authenticated photographs of Jill are known to exist today. The image shown here is an official age-progressed composite created by the National Center for Missing & Exploited Children (NCMEC), developed to represent what Jill may have looked like as an adult.

Jill's disappearance remained hidden for decades until DNA testing revealed Jack's true identity in 2012. Today, finding Jill—or discovering what happened to her—has become the central mission of The Fronczak Files and the Jack & Jill Rosenthal Foundation, making her one of the longest-missing children whose story is still actively being investigated.