mbles) - [Betty Ann] We used to camp right across the water over here.

It was his special place and mine, too.

- [Pamela] For Betty Ann Waters, looking out on Burrillville's Echo Lake, the echoes of the past still reverberate.

Here she can reflect on the astonishing odyssey that has consumed more than half her life.

- I think how much he loved me.

He was the person in my life that believed in me the most, ever.

- [Pamela] He was her brother, Kenny Waters, just one year older.

They were two of nine children living on their grandfather's vegetable farm in the small town of Ayer, Massachusetts where Fort Devens was based.

- It was a lot of fun growing up in Ayer.

It was a very small town, it was an army town.

We didn't have a lot of neighbors back then, but we didn't need them because we were our own baseball team.

- [Pamela] And of all her siblings, Betty Ann was closest to her brother Kenny.

- And we just did everything together.

It was like we were best friends.

You know, we used to skip school together and we'd go just running through woods making tree houses and, you know, kinda just a farm life.

- But she admits her brother was mischievous.

He was no choir boy?

- No.

- [Pamela] Kenny was often getting into scrapes and, once, a knife fight.

He served in the Army, though, and eventually became a short order cook at the now-closed Park Street Diner, the place the community and the police went for coffee.

- And Mrs. Brow was a regular there.

Her friend worked at the diner.

I mean, it's a very small town, so everybody knows each other.

And Kenny used to see her and say hi to her and, you know, there was never any problem.

- [Pamela] But there was a problem for Katherina Brow, a fatal one, on a May morning in Ayer in 1980.

- We get a phone call from Kenny saying that Mrs. Brow was murdered.

And we're like, "What?"

- [Pamela] 48-year-old Brow, a neighbor of the Waters', was found in her trailer home, stabbed 30 times, in a violent robbery of cash and jewelry.

Kenny's live-in girlfriend was deeply distraught because-- - They asked him to come down to the police station to check out his alibi.

- [Pamela] He was cleared, eliminated as a suspect.

The case went cold.

But two years later, Kenny's now former girlfriend had a new boyfriend who called Ayer police.

- And he wanted to sell information to them.

And he gave them a story that his girlfriend knows that it was Kenny because she was living with him at the time and he came home that morning full of blood.

- Kenny's blood was O+, the same as the killer's.

But in the early eighties, there was no DNA testing.

Police claimed fingerprints left at the scene were unusable.

Betty Ann contends there was police misconduct in their eagerness to solve the vicious crime.

So did you ever believe that your brother could be guilty of such a crime?

- No, no!

- [Pamela] Why?

- Because it's just not his nature to go wanna rob somebody and kill them.

- Despite her conviction, her brother was falsely accused.

Kenny was indicted and later found guilty of murder just a few hours after a five day trial in 1983.

Yeah, so your heart dropped when they said, "Guilty?"

Oh my God, yes, 'cause we figured they would all see through all of it.

We thought he was coming home and we already planned dinner.

- [Pamela] 29-year-old Kenny Waters was sentenced to life in prison without parole.

Inmates nicknamed him Muddy Waters because he suffered such severe blues.

Betty Ann remained in close contact, both frustrated by five years of unsuccessful appeals.

Suddenly Kenny stopped calling.

- He finally calls and I found out that he tried to commit suicide.

(sighs) Anyway, when he lost that last appeal, he cut himself.

I still can't talk about it.

- [Pamela] But she can talk about the major decision that would shape her future, becoming an attorney with a sole client, Kenny.

- So in our conversations, that very conversation, he said to me that he's never getting out of there unless I went to law school.

(laughs) - He told you that?

- Oh yeah, he did.

He said, "The only way I'm getting outta here is if you, Betty Ann, go to school, you go to law school, you be my lawyer."

And so it became a promise that, I promise I will do whatever I have to do to get to law school if you just stay alive.

- [Pamela] To keep him alive, Betty Ann, a single mother living in Bristol, worked as a bartender at Aidan's Pub while earning an undergraduate degree.

After being accepted into Roger Williams University's School of Law and beginning her studies, she discovered the Innocence Project, an organization that works to exonerate the wrongly incarcerated.

- And I learned about DNA and I'm like, "Wow."

I know there was a lot of blood in my brother's case.

I don't know if it still exists, but there was, and this could be the holy grail I'm looking for.

- [Pamela] Against all odds, she graduated, passed the bar exam, and 12 years later, as her brother's lawyer, she went after the evidence and was told it had been destroyed after so long.

That didn't stop her.

She persisted and finally, a clerk from the Middlesex County Courthouse, where Kenny was tried, returned her call.

- She goes, "Well, we did find a box," with my brother's name on it, and I'll never forget it, like, it was just this old corrugated, a dollar Staples box, you know?

They opened it up and I saw the plastic bags with the evidence I was looking for, like the material from that linen closet that had blood on it.

- [Pamela] She filed a motion to protect the evidence, then contacted the Innocence Project to test that DNA.

- And of course it comes back that it's not Kenny.

- [Pamela] So after 18 long years as a prison inmate, Betty Ann called her brother to say, "Promise kept."

- And I said, "Kenny, you wanna come home tomorrow?"

And, yeah.

Yeah.

- [Pamela] What'd he say?

- Yeah, you know, he was like, "What?

What are you talking about?"

I'm like, "No, tomorrow."

And, uh-- - What was that moment like when he walked up?

- Aw, it was crazy.

To think about it even today, it's, like, unbelievable.

I think that we were just beaming from ear to ear and didn't even have to say anything, you know?

- [Pamela] But her brother did have one thing to say.

- I think it's absolutely amazing that she's dedicated her life to this.

- [Pamela] Kenny Waters was a free man and a famous one.

Betty Ann and her brother were instant media celebrities on Oprah and all the morning shows.

- We had an absolute ball.

We had the, he had the best time of his life.

- [Pamela] But that joy would be short-lived.

Just six months after his prison release came another cruel twist of fate.

Kenny was walking to his brother's house in Middletown taking a shortcut when he fell off a wall and died from brain injuries.

Betty Ann, though grieving, says that half year together, some spent here on Echo Lake, was a saving grace.

- He died innocent and free and he was surrounded by his family, not leaving in a pine box in prison.

- [Pamela] And Betty Ann continued to be her brother's keeper, by giving him another measure of justice.

She sued the town of Ayer's Police Department and his estate was awarded millions.

Now, if this all sounds like the plot of a Hollywood movie, it is.

- [Foreperson] We find the defendant guilty, Your Honor.

(gavel bangs) (sighs) - We'll get you out, Kenny, you hear me?

- [Pamela] In 2010, actress Hillary Swank portrayed Betty Ann Waters in the film "Conviction"-- - Super proud of her!

- Based on the true story.

- To be talking about this film early.

If we can DNA test the murderer's blood, it'll prove Kenny's innocent.

- [Pamela] Still, Betty Ann was haunted by one more thing, finding the real killer.

The tool, forensic investigative genetic genealogy, a complex system matching DNA to a family line.

- I have a couple of plans right now to try to maybe figure out through the profile.

- [Pamela] And just a week after our conversation, this happened.

- Today, there was a major breakthrough in this case after it went unsolved for decades.

- We're able to determine, to an overwhelming statistical likelihood, that one of those brothers, Joseph Leo Boudreau, was the source for the DNA that had been left at the crime scene.

- Joseph Leo Boudreau, long deceased and formerly of Massachusetts, was identified as the real murderer through genetic genealogy.

After all this time, after all you went through, and now this.

- Yeah, I can't even believe it happened.

I had goosebumps throughout my entire body and I was like, "What?"

The first thing I wanted to do was call Kenny.

- [Pamela] Her beloved brother, their enduring bond.

Just one more incredible, indelible chapter of their story.

- I never imagined this and everything along the way, I really never imagined until it was over.

Then I can look back a little bit and say, "Oh, wow, that happened."

- [Pamela] If you could talk to him today, what would you say?

- [Betty Ann] I love you.

That's it.