A henderson man who learned 5 years ago that his name, birthdate, and genetic history were all wrong..

Says he now knows many of the details of his life and family history.

((denise valdez)) the i-team first broke the story about paul fronczak four years ago this week.

Since then -- the strange tale has been reported all over the world.

It involves an infamous kidnapping, a nationwide manhunt, and a lot of heartache.

((dave courvoisier)) the i-team's george knapp is here with the latest developments.

((george knapp)) >>> the last time we heard from the man known as paul fronczak, he was hot on the trail of clues about his birth family, and was estranged from the parents who raised him.

Since then, he's had face to face encounters with long lost relatives, has patched things up with his adoptive parents, and has learned the hard way about that old adage--be careful what you wish for.

((george knapp)) as he entered a new jersey trailer park and approached the home of a woman he believed to be his sister, paul fronczak was excited and apprehensive.

Paul fronczak i knocked for about 15 minutes and nobody answered.

And i wasn't going to give up.

I just kept knocking and finally i saw movement and then she came and opened the door and i said "i'm paul.

I'm your brother."

And she said, "i know who you are, come on in."

((george knapp)) his face-to-face with his long lost sister was a temporary high point in a roller coaster journey that began in 2012 when a drug-store dna test confirmed that paul wasn't a fronczak after all.

He'd been raised in chicago by loving parents, who were hurt by the news about the dna test.

Paul fronczak: we didn't talk for almost 3 years.

It was pretty bad.

My mom took it like i wanted to find new parents, i wasn't happy with them but that couldn't be further from the truth.

My parents are amazing parents.

They made me who i am, and i wanted to do the best i could and that would be to find their real son.

((george knapp)) his suspicions were first aroused at age ten, when he found a hidden stack of news clippings which told the sensational story of the 1964 kidnapping of newborn paul.

A woman dressed as a nurse somehow walked out of a chicago hospital with the baby, setting off a frantic nationwide manhunt.

But the kidnapper and victim were never located.

More than a year later, a boy was found abandoned on a street in newark new jersey on the same spot this recent photo was taken.

The mystery boy was given the name scott mcckinley.

Evidence linking him to the fronczak's was slim, but he was adopted and raised as paul.

After our story first aired in 2013, other media around the world picked it up.

The fbi reopened the kidnapping case, and tips poured into this facebook page.

Geneology researchers volunteered thousands of hours to solve the dual mysteries.

A dna match was made to a cousin, alan frisch, then to alan's biolopgical father, lenny rocco, a former boxer and doo-wop singer.

Through lenny, paul was welcoemd by other blood relatives.

He even performed with cousin lenny's band.

Paul fronczak: he was best friends with my dad, my biological dad.

((george knapp)) it was dna detective cece moore who first told paul that his birth name was jack, and his family name.

Paul rosenthal george so your name is jack rosenthal?

Paul jack thomas rosenthal.

I was jt.

((george knapp)) paul's father was gilbert rosenthal.

His mother was named marie.

Both are now deceased, and paul visited their gravesites.

The more he learned, the darker the story became..a death certificate shows the father had worked in law enforement on the boardwalk in atlantic city.

Family members say he had connections to mobster nicky scarfo, and was not well liked.

He was in the military in the korean war.

When he came back he was a very mean guy.3951 from talking to my real sister, and she said that when he died, nobody went to his funeral, not even his wife.

((george knapp)) this is the only known photo of paul's mother, pregnant with him at the time it was taken.

She wasn't a model parent either.

My mom was a heavy drinker, very abusive.

I haven't heard good things about either parent.

((george knapp)) there were five rosenthal children.

One sibling had died.

A sister, two years older, initially was excited to reconnect, then abruptly cut off all contact.

A brother, one year younger, did the same after paul spoke to him by phone.

Paul fronczak: i can't wait to meet you, this is great, then all of a sudden, he sent an email that said i want nothing to do with you, i don't believe you.

I think it's a scam.

Don't ever contact me again.

((george knapp)) but there was another, bigger surprise still lurking.birth records show that jack rosenthal had been born a twin.

His sister was named jill, but she vanished at a young age.poof, just gone.

Paul: she might have been dropped off, and she's alive and well, and if she is, i'm going to find her.

Still feel that something tragic happened because why would you abandon your twins when you have two older children?

((george knapp)) >> the disappearance of his twin sister jill sparked a new round of digging by paul...literally and figuratively.

He also has new clues about biological paul, the boy kidnapped from the hospital, and he's written a book about his journey.

It's called "the foundling".

Tonight at 11, we will have the story of the search for jill, an update on what the fbi has been doing, and a look at the new book.

Our website has many links to materials related to the fronczak mysteries./// tedd florendo (((>>>cool