Megan's father, Eugene Church, took what's known as a Y-DNA test.

It traces a man's direct male lineage by identifying the genetic signature that is passed down from father to son across generations.

If Green was in fact the son of Solomon Moxley, and if descendants of other Moxley men are in the database, then Eugene's test would match him to those men and bring our mystery to a close.

You ready?

Yes.

Please turn the page.

Would you read the number of men we found who were Moxleys?

Zero.

Zero.

None of 'em.

So you know what this means.

Not a Moxley.

Forget- Megan Moxley.

Megan Moxley.

You don't have to worry about that.

Not Megan Moxley, okay.

Didn't sound right in your mouth.

Well, it wasn't right in fact.

Solomon Moxley was not Green's biological father.

Okay, wow.

Yeah.

So how are you feeling right now?

See- I wanna know who it is!

I wanna know!

To learn the identity of Green's father, we needed some luck, and fortunately we got it.

The same Y-DNA test that showed Megan's father had no matches to anyone named Moxley, also revealed that he did have a significant number of matches to men with a different surname, the surname of Green's biological father.

You can see it on the right of the chart, would you please read it out loud?

Halsey.

I've never heard that.

Sorry.

I've never heard that, ever.

We thought Holtz.

We thought... We had heard a couple different names, but never Halsey.

Mm-hmm.

Wow.

Halsey.

Everyone was wrong.

We were all wrong.

How does Megan Halsey sound to you?

It sounds...

I guess it sounds right.

It sounds right.

Wow.

I wanna know who he is and how he met her, and... That's amazing.

My vision's all blurry.

I can't see.

Oh.

Wow.

We don't know how Caroline met Green's father, but we were able to figure out who he was.

Using the same techniques that we'd use with Terrie Morrow, we searched publicly available databases for people whose DNA profiles matched Megan's father's.

Eventually we focused on a small cluster of individuals who had Halsey ancestors and who also shared enough DNA with Megan's father to be a half second cousin, meaning they all shared a great-grandfather, a man who had to have been Green's biological father.

William Cleveland Halsey.

That's him.

You just met Green's father.

Wow, William and Caroline.

Hm.

I'm speechless.

We've wondered about that for a long time.

Wow.

William Cleveland Halsey.

Mm-hmm.

What do you think your dad's going to say when he learns this?

He's gonna cry.

He's gonna cry.

Once we'd identified William by name, we could research his life.

We discovered that he was a farmer who lived in Piney Creek Township, North Carolina, just about 10 miles from where Caroline was living when Green was a boy.

And though we don't know anything more about the two of them, census records show that by 1900, William had a wife named Melinda Halsey, and they had two young sons.

He had another family.

And what year was this from?

1900.

1900.

Wow.

So, wait, he had another family.

He had a four-year-old and a three-year-old in 1900.

That's right.

And when was Green born?

Green was born in 1895.

Right, so Green was five.

Yeah.

So technically he had a five-year-old, a four-year-old, and a three-year-old.

Right, and maybe Rufus.

Yeah, and maybe Rufus.

We don't know.

Wow.

Wow.

I was fully prepared to come here and be angry at him.

I was prepared to be angry, you know?

Are you angry?

No, I'm not angry.

I'm curious.

I wonder how they met.

I wonder what the nature of their relationship was or if, you know, like that kind of thing.

But I was fully prepared to come and be angry.

But you're not.

No, not at all.

So why aren't you angry?

I'm not angry because I, you know, they may have had two children together.

We don't know, you know?

It may have been an actual like, relationship of some sort.

And then faded away.

Yeah.

Which happens.

Yeah.

Hm.

That's something.