We now attempted to trace Samuel's roots, but immediately hit a wall.

There were no records to take us past his parents.

Fortunately, we had more success with his wife, Dorothy.

We were able to trace back from her to Lena's great-great-grandmother, a woman named Regina Seltenwirth.

Regina immigrated to New York when she was 14 years old.

And married when she was 19.

Her marriage record indicates that she was born in a place called Tarnów, which is now in Southeastern Poland.

This proved to be a gold mine for our researchers.

In Tarnów's archives, we found Regina's school records offering Lena a precious glimpse of her ancestors' childhood.

- That's beautiful.

- Isn't that amazing, - Amazing.

- that that still survives?

It's amazing.

She was attending an all girls elementary school.

What a little cutie.

What's it like to see that?

It's incredible.

I mean, to think of her as a little girl who has not yet come to America, who has not yet given birth to the child who will then give birth to my grandmother, it's beautiful.

Well, Regina made the journey to America while her parents stayed behind in Tarnów.

And that means she likely never saw them ever again.

- Wow.

- Can you imagine when you were 14, your parents would put you on a boat?

- No, I can't.

- And they go, "We'll follow."

- And they never did.

- And they never did.

Wow.

This story was about to darken significantly.

Records show that Regina left at least 11 siblings behind in Europe.

We don't know what happened to them all, but one of her brothers, a man named Moses Seltenwirth, moved to Hungary.

And was living there with a wife and children when World War II broke out.

The family was soon split up.

And Moses's daughter, Ilona, was sent to a place called Kamianets-Podilskyi, where she met a terrible fate.

Wow.

Between August 26th and August 28th, 1941, Kamianets-Podilskyi was a site of a horrific crime.

The SS rounded up newly-arrived deportees, and together with the local Jews, marched them to the outskirts of town and murdered them on the spot.

Over three summer days, it's estimated that 24,000 Jewish people were murdered.

- Wow.

- And more than half of them were Hungarian Jews.

Miraculously, Regina's brother Moses, along with his wife and son, somehow managed to survive the Nazi terror.

They appear on a list of Hungarian Jews compiled by Allied soldiers at the end of the war.

But Ilona is missing from this list.

And we found no trace of her in any post-war document.

It's an amazing thing to see those names and to know that they're a part of our family, but to also know that they had to spend the rest of their lives with this other person who was so important to them missing, and wondering about her fate.

Must have made surviving a very complicated thing.

Oh yeah, absolutely.

As it was for everyone who survived.

Yeah.

So what's it like to even begin to contemplate that you have a genetic connection now to the Holocaust, of which you weren't aware?

It's an incredibly painful thing to think about people with whom I share, probably not just DNA, but, you know, features and emotional responses, and an approach to life, those people being placed in this situation, and having their lives extinguished this way.

I don't think there is a way to, there's not a way to reckon with it.

It's too big and it's too, and the whole act is too vast.

But to see a personal connection to it, literalizes it in a way that's very, very powerful.