The story begins with a 1950 census for Philadelphia, where we found Sanna's father as a four-year-old boy, living with his single mother and older brother, a time of his life that he rarely discussed.

What's it like to think of your father as a four-year-old?

I got emotional just now.

It's surreal, 'cause he's always been such a, you know, a serious, you know, he's the head of the family.

He's a director.

He's in charge.

And so to think of him as like a little... A vulnerable little boy.

Yeah.

Yeah.

It's emotional.

When this census was recorded, Sanna's father was being raised by his mother, because his father, a man named Stanley Edward Lathan, had left the family, and no one knew where he'd gone.

We found Stanley in the 1950 census for Boston, working in the kitchen of a restaurant and living in what was known as the Rufus Das Hotel for Men.

Wow.

That's wild.

I mean, it looks like they were workers.

That looks like a place where you come to work.

Well, you're right.

The hotel your grandfather was staying in was something between a boarding house and a homeless shelter.

Mm.

It provided dormitory facilities at a nominal fee.

Every time he wanted to stay there, he would register for a bed in the evening, then check out in the morning, every day.

Wow.

Likely to go to work at the restaurant, where he was working in the kitchen, and then repeat the process all over again to keep a roof over his head.

Did you have any idea?

Nothing.

I know nothing.

Of what had happened to your father's father?

No, I mean, I knew he did struggle with alcoholism, and that was, that's all that my grandmother told me, but other than that, I didn't know anything.

We now tried to trace Stanley's roots, and encountered a mystery even bigger than his life.

Records show his father was a man, named William Edward Lathan, and that he was born in North Carolina in 1880 to a woman named Caroline Lathan, but that's where the paper trail ends.

Despite our best efforts, we could not name William's father.

There was only one hope left, DNA.

So we reached out to Sanna's father and focused on his YDNA, the type of DNA that is passed virtually intact from father to son, across generations, and it led us to a startling discovery.

Sanna's father's line leads directly to a White man with a surname Sanna had never heard before.

Male of likely European ancestry with the surname of Slade, Slade.

Slade, S-L-A-D-E?

Mmhmm.

According to your father's DNA, your father's biological surname, and thus yours, is Slade.

It is not Lathan.

I like Lathan better.

I like the name, I like that way it rolls off the tongue.

Sanna Slade.

Sanna Slade?

Sorry, Sanna Slade.

No, I don't know.

It sounds like a stage name, Sanna Slade.

Maybe that'll be my new alias when I, you know, stay in a hotel.

Yeah, there you go.

We now knew that William's father was a Slade.

We also knew that he was a White man who had fathered a child with a Black woman sometime around 1880, but his full name still alluded us.

So we turned back to Sanna's father's DNA and started looking for matches in publicly available databases, hoping to find clues that would lead us to the final piece of the puzzle.