When a one-day-old baby, Paul Joseph Fronczak, was stolen from a Chicago hospital in 1964, the terrible story made headlines across America. Then, two years later, an abandoned boy was identified as the missing baby and handed over to the relieved parents. Years later, Paul began to investigate what had happened - and was shocked by what he found.
Paul Fronczak was 10 when he went hunting for Christmas presents in his parents' basement. He pushed aside a sofa to get into the crawl space. There, he discovered three mysterious boxes full of letters, sympathy cards and newspaper clippings. One headline read: "200 search for stolen baby." Another: "Mother asks kidnapper to return baby." He recognised his parents in the pictures, looking distraught and much younger. Then he read that their baby son, Paul Joseph, had been kidnapped.
"Wow, that's me!" he thought.
It was a sensational tale. On 26 April 1964 his mother, Dora Fronczak, had given birth to a baby boy in the Michael Reese hospital in Chicago. She had nursed the baby throughout the day - when he wasn't sleeping with other babies in the nursery. But the following morning a woman dressed as a nurse came into Dora's room and took him to be examined by a doctor. She never returned.
Hospital staff realised something had gone wrong, and a frantic search was soon under way. However, the hospital didn't notify the authorities - or the baby's parents - until that afternoon. At 3pm they called the father, Chester Fronczak, at the factory where he worked as a machinist.
"My dad had to leave work, go to the hospital and tell his wife that the baby was missing," says Paul. "You think you're safe - you're in a hospital - and that's where your baby is kidnapped."
The biggest manhunt in Chicago's history was then launched, involving 175,000 postal workers, 200 police officers and the FBI. They had searched 600 homes by midnight, but to no avail.
Excited by his discovery, Paul ran upstairs with a handful of clippings to ask his mother if they were about him.
Dora reacted angrily, telling him off for snooping. Then she admitted: "Yes, you were kidnapped, we found you, we love you, and that's all you need to know."
Paul knew not to bring up the subject again, and he didn't - for another 40 years.
But his curiosity was not satisfied and often, when he was alone in the house, he would sneak back into the crawl space to read more.
That was how he learned about the next part of the story - how he came to live with the Fronczaks.
After the kidnapping, Dora and Chester stayed in hospital for a week, waiting for news. When they returned home, they were hounded by the press. Despite all the publicity, there were no credible leads - their baby had disappeared without trace. The investigation was quietly shelved.
Then, in March 1966, nearly two years later, Dora and Chester received a letter from the FBI - a toddler had been found in Newark, New Jersey, who matched their son's description.
The boy had been abandoned in a pushchair in a busy shopping centre the previous July and had been placed with a foster family, the Eckerts. They had baptised him Scott McKinley and were so fond of him they were considering adopting him.
Before they could, however, a New Jersey police detective had the idea that the boy might be the missing baby from Chicago.
The FBI began to test that hunch. There wasn't much to go on - there was no record of Paul Joseph's blood type, nor had the hospital taken the baby's fingerprints or footprints. All they had was a single photograph taken on the day he was born - and the shape of the baby's ear in that picture was very similar to that of the abandoned toddler.
"They ended up testing over 10,000 boys that could possibly be Paul, and I was the only one they couldn't fully exclude," says Paul.
The Fronczaks were elated to hear the news. "Back then the FBI was the elite authority, and when they tell you something you believe it," says Paul.
Three months later they drove from Chicago to meet the boy who might be their son in the offices of the New Jersey children's services. All three had been put through a series of psychological tests before the meeting. Dora and Chester had also had to be approved to adopt the child now officially known as Scott.
"An FBI agent walked me in and they let us get acquainted for a while," says Paul. "My mum had only spent less than a day with her son before he was taken out of the hospital. And then, years later, she sees this child."
Dora has since told Paul that she felt the world was watching her.
"She could either say, 'I'm not sure,' and put this child back into the system, or say, 'Yes, that's my son,' - and even if it was not, save this child from what could be a horrible life."
Dora said it was her son.
"She did what she thought was right, and I'm glad she did," says Paul.
They took him to Chicago and formally adopted him.
The Fronczaks were loving parents, if - understandably - over-protective. Sometimes, that led to clashes. Paul was sent to a Catholic school with a strict dress code, but he liked rock music and wore his hair long.
Once, during a heated argument over the length of his hair, Dora said: "I wish they'd never found you."
That stuck with Paul. "Even to this day just thinking about it, I feel it in my soul," he says.
After graduating from high school, Paul left home to be a bass player with a rock band in Arizona. Five years later, when the band broke up, he returned to Chicago but soon got restless and joined the army for a year. Afterwards he moved around, working as a salesman and, later, as a model and actor. Eventually he settled in Las Vegas.
"I moved probably at least 50 times in my life and I've had well over 200 jobs. And no matter where I go or what I do, I've always had those paper clippings with me," he says.
In 2008 Paul married for the second time and soon he and his wife, Michelle, a teacher, were expecting a daughter. Paul was delighted. But when the obstetrician asked about their families' medical histories, it hit Paul that he wasn't really sure how to answer.
Ever since finding out about the kidnapping, he had wondered if he was really his parents' son.
"I actually thought: 'What are the chances of me being this one baby taken from Chicago?'
"I was found so far away, it just seemed so unfathomable."
He had always felt that he did not fit in. His parents seemed closer to his younger brother, Dave. They were all quiet and reserved, whereas Paul liked loud music and fast motorbikes. They looked different, too.
"Dave looked exactly like my dad - mannerisms, facial expressions, the body-build, everything. And I looked like neither."
Now the question began to haunt him - was he really the stolen baby?
"For years I had wanted to do a DNA test with my parents," says Paul. "Not because I wasn't happy, I just wanted to know the truth. I had always found a reason not to do it - I didn't want to hurt them - but there came a point when I needed to know."
He had also been put off by the expense. But one day in 2012 Paul spotted over-the-counter DNA kits for sale and bought some.
When his parents came over from Chicago for a visit, Paul plucked up the courage to broach the subject, about an hour before they were due to leave.
"Have you ever wondered if I'm your real son?" he asked. Caught by surprise, his parents admitted that they had. "Would you like to find out?"
Minutes later, everyone had swabbed their cheeks and the kits were sealed. Then Paul took his parents to the airport.
But by the time their plane landed a few hours later, Dora and Chester had changed their minds. They rang Paul, asking him not to send off the kits - he was their son, and that was the end of it.
"I kept those samples in my desk drawer for a couple of weeks," says Paul. "I wrestled with that every day because I love my parents, I wanted to respect their wishes, but sometimes you just have to do what you feel is right. How can you be wrong, trying to find the truth?"
So he sent the samples off.
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He was at work when he got a phone call about the results. After answering some security questions he was told there was "no remote possibility" that he was Paul Fronczak, Dora and Chester's biological son.
"I just felt like my life as I knew it was ended. I felt the colour drain from my face. I couldn't think. I got all sweaty," says Paul.
"Everything I thought I knew about myself - my birthday, my medical history, being Polish, being Catholic, even being a Taurus - went out the window, and for a second I didn't know who I was."
The results raised two urgent questions. Who were Paul's parents, if not Dora and Chester Fronczak? And what had happened to the real Paul?
Before he had even told his parents the news, Paul called a local investigative journalist, George Knapp, to ask for help. Soon Paul Joseph Fronczak was a national news story once again.
His family - who shunned the media - were furious, and didn't speak to him for over a year.
"You've got to understand, the main reason I did this was to find my parents' real child," says Paul. "They were the most amazing parents. The best gift I could give them would be to find their kidnapped child, and I thought the best way to do this would be to invoke the help of the media."
One consequence of going public was that the FBI reopened the Fronczak kidnapping case. They had located 10 boxes full of original case files in Chicago - but because the DNA results proved that he was not the stolen baby, Paul had no right to see any of it.
He did, however, speak to one of the retired FBI agents who worked on the original case, Bernie Carey, who admitted that some of the team had not been convinced they had found the right child.
Paul had more luck with the search for his biological parents.
A team of volunteers called the DNA Detectives took on the case free of charge. Led by the genetic genealogist, CeCe Moore, they used a combination of DNA testing and classic investigation techniques: searching newspapers and public records, trawling through social media, and endless phone interviews.
Although Paul had been found in New Jersey, they traced his family to Tennessee. Meanwhile his DNA test had revealed Ashkenazi Jewish roots.
"I knew one side of the family had to have a Jewish grandparent," says Moore.
But there were also many setbacks. It was months before they made their breakthrough - a conversation with one of Paul's potential relatives, who mentioned that there were some missing twins in the family.
"That's when we knew we were finally heading in the right direction," says Moore.
It was on 3 June 2015, two years after they had begun their investigation, that she spoke to Paul on the phone.
"What do you think of the name Jack?" she asked him.
Paul said, "It's a strong name. It's a good name."
Moore said, "Well that's your name."
That was how he found out he was born Jack Rosenthal, and that he was six months older than he had always thought - his new birthday was 27 October 1963.
And there was a kicker: he had a twin sister, Jill. But she, like him, had vanished. So now Paul had a third person to find.
"I don't think you could hear that you have a twin, and not seek that person for the rest of your life," says Moore.
Meeting his relatives was exciting at first.
Paul, who had always been drawn to music, was delighted to discover that his cousin, Lenny Rocco, was a musician too - he had been a doo-wop singer in the 1950s.
"To me, that really proves that you don't have to be raised by your real parents to have those same qualities and traits - like musical ability, I was never exposed to it, but I was drawn to it," says Paul.
"I've played in bands all my life, and when I got to meet my real family, I got to sit down and play with Lenny's band."
Moore, who has reunited thousands of families, sees this kind of thing all the time.
"People meet each other that were raised in completely different households and there are so many similarities," she says.
"It's not just how they look, it's the choices they've made in life - who they've married, what they've named their children, what occupation they chose, even down to the oddest details, like the password on their phone. I do believe that much more is coded in our DNA than we realise - it can't be coincidence."
But not all of his relatives welcomed him with open arms, and Paul soon discovered there was a dark side to his biological family. His mother, Marie, had been a heavy drinker, and his father, Gilbert, had come back from the war in Korea "an angry man".
There is evidence that Paul and his twin sister Jill - who had two older sisters and a younger brother - had been badly neglected. They were always crying, the family says, and one cousin remembers seeing the babies sitting "in a cage".
Nobody knows exactly what happened, but whenever family members asked about the twins they were told that another member of the family was looking after them - when in fact it seems that no-one was.
Paul thinks that "something tragic" may have befallen Jill, and that that may have prompted the decision to get rid of Jack, "because they couldn't explain just one twin".
In his book, The Foundling, Paul describes the twists and turns of his obsessive - and sometimes daring - search for answers. At one point he digs up the garden of the house where the Rosenthals had once lived, hoping in vain to find the remains of his twin sister.
"My real parents were really not very nice people. I'm thankful that they abandoned me because it allowed me to be with the Fronczaks. They saved my life," says Paul.
Two years after their fall-out over the DNA results, Paul made peace with his adoptive parents, and for the first time he sat down with them to really talk about what happened. Dora told him what she had been through.
"I know now that those events shaped my mum into the way she is today," says Paul. "My mum has this never-ending guilt of handing Paul over to the nurse. Even though she knows that in a hospital that's what you do - the nurse says, 'We need your baby,' you hand the baby over. But it's something that she's wrestled with her whole life."
Dora also gave Paul a photo album and letters that had been passed on by the Eckerts, the foster family who had looked after him for a year and baptised him Scott McKinley.
"My mum had this photo album all my life and had never even mentioned it. It makes me kind of misty because these are the first pictures I have of me being a child. Even my real family have no baby pictures of me - my grandmother had a photo album with all the kids in chronological order, and the page with the twins on it was ripped out."
Paul's father, Chester, died last August, but Paul speaks to his mum every couple of days. Dora will be 82 on 27 October - coincidentally, they now share a birthday.
Dora has mixed feelings about the book. "She wishes that I hadn't been quite so open and honest about everything," he says. "But I wrote an honest book."
Paul is as determined as ever to find out what really happened to Dora's son. He still has a private investigator working on the case, and says the next step is to exhume a body.
In fact, he wants to exhume two bodies.
"We have a really strong lead on a possible biological Paul - and the other is possibly my twin sister."
Exhumation is a complex and costly process, but Paul is undeterred. There are still many unanswered questions.
"The story is by no means anywhere near finished," he says.
He and his second wife are now divorced, although still good friends. Paul admits that his obsession with the investigation may have contributed to their break-up.
"It got to the point where every waking minute I was doing something involved with this search," he says. He regrets nothing, however.
"This was something that I had to do. It has made me feel more at peace."
It has also helped him to understand things about himself, such as why he could never seem to settle down.
"The first couple of years of my life really shaped who I am: I'm able to walk away from anybody, any job, any situation and never look back. I think that's part of having three childhoods, three identities at such a young age. It's about adapting. It's about survival. It's about getting to the next day."
CeCe Moore also wonders how all this affected the young Paul. She is curious about what happened to him in the months when he was reportedly being examined by the FBI.
"What made them come to the conclusion that he was Paul Fronczak? Were there signs of trauma that perhaps were misinterpreted as a baby that had been kidnapped, rather than a baby that had a somewhat abusive life?" she asks.
Paul's daughter, Emma, is now nine - she thinks it's funny to call him Jack, and sometimes does, to tease him. But he has decided not to change his name yet.
"I'm going to stay Paul until they find Paul. The day I find Paul, I'm going to hand him his birth certificate, and I'm going to claim mine."
Paul Fronczak was a guest on the Jeremy Vine show on BBC Radio 2
Paul Joseph Fronczak is co-author with Alex Tresniowski of The Foundling - the true story of a kidnapping, a family secret, and my search for the real me.
He would like to hear from anyone who might have information about his case, through his website.
All photographs courtesy of Paul Fronczak unless otherwise stated
The FBI declined to comment.
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