“48 Hours” probes 2011 disappearance of Tennessee mom Shelley Mook

Produced by Chuck Stevenson, Michelle Feuer and Taigi Smith

CENTRAL TENNESSEE — “Back when all this happened … I remember hearing the story about the car being found out in the field, and that it had been burnt,” Chief Larry Farley, of the Rutherford County Fire and Rescue Department, told CBS News correspondent Michelle Miller.

Firefighters remember the night back in 2011. It was 12:30 a.m. and in an empty farm field outside of town, a car went up in flames.

Shelley Mook’s burnt out car — a Pontiac Grand Prix — was found miles from her home the morning after her disappearance. Kevin Keele

“Normally people wouldn’t think it was a big deal but …This is something that we deal with quite often,” Farley explained.

“A lot of times people will steal a car, go joy riding … and then, when they get through with it, they’ll take it out in the country somewhere, and set in on fire, burn it — and then walk off and leave it,” the chief continued. “Just another car.”

But it wasn’t just another car. It would turn out to be a clue — a clue that could lead to a murderer.

In Central Tennessee, 20 miles down the road from that mysterious car fire, something else strange happened. At a middle school in Shelbyville, an eighth grade teacher named Shelley Mook never showed up for class.

“This is not something that you ever expect to happen in your life– to have somebody that goes missing,” said best friend Brittany Brooks.

“What do you think happened to her?” Miller asked.

“It’s really hard to say,” Brooks replied. “I mean not having found very much evidence or, I mean, there are so many possibilities.”

Brooks grew up with Shelley Mook.

Best friends Brittany Brooks, left, and Shelley Mook Brittany Brooks

“She had these amazing eyes,” Brooks said. “…beautiful smile. We always called it the million-dollar smile.”

After Shelley’s divorce in 2009, they became even closer.

“Were you her lifeline outside of the marriage?” Miller asked Brooks.

“I think part me, and part her mother and her family,” she replied. “…neither one of us had sisters and it was kind of the sisterhood.”

“She was a loving person. An amazing mother,” Brittany Brooks said of Shelley Mook, pictured with daughter Lilli. “For her just to be gone — to vanish — it’s not like her.” Brittany Brooks

Shelley, 24, also loved her daughter, 6-year-old Lilliana. They called her Lilli.

“Shelley would never abandon her daughter, she would have never left her without saying goodbye or kissing her goodbye, and she did that day,” said Brooks.

That day was Monday, Feb. 28, 2011.  And just one person would tell police what happened in the house that afternoon. That was Shelley’s ex-husband, Tyler Mook, the father of their daughter. They had been divorced a couple of years.

“Tyler’s very smooth,” Brooks explained. “He had this mysterious dark way about him … He was absolutely — he was definitely more than just a bad boy.”

Brooks and Shelley met Mook back in high school.

“Shelley and I … were like, ‘Oh, you know, take a look at who just walked in. We don’t know him, but we wanna know him,'” she recalled.

All that happened up in Pennsylvania, where Shelley and Brittany grew up.

Tyler Mook was a bit older. He liked engines and cars and he liked girls.

“Were you there when Shelley walked over to him?” Miller asked Brooks.

“We meet him at a party one night and her and I kind of made bets to see who could end up going out with the cute guy that we don’t know,” she replied.

“So was he intrigued?” Miller asked.

“Yes,” said Brooks.

“She was intrigued?”

“Uh huh,” Brooks replied. “It was definitely a few months and that was it. She was hooked and he was hooked.”

After high school, Shelley and Tyler got married. They had their daughter and moved down to central Tennessee to be closer to Tyler’s family. Everyone said family was important to Tyler Mook.

“Did you ever feel that he loved her?” Miller asked Brooks.

“Absolutely,” she replied.

“She loved him?”  Miller asked.

“She did, she did,” said Brooks.

“In the beginning, was the marriage — was it a good one?” Miller asked.

“When it was good it was really, really good. When it was bad, it was really bad. There was no happy medium,” said Brooks.

There were some problems at home, like allegations of cheating.

“Everyone has their troubles, but it seemed like he genuinely loved her,” said Brooks.

The couple had an on-again, off again relationship, and when they finally divorced in 2009, Tyler kept trying to get back with her.

This is the letter he wrote to Shelley:

“Shelley my Love…

Congrats on your first full day of teaching…

My love for you grows like a wildfire…

I’m polishing myself for you”

He also tells her he’s going to take her for a Caribbean cruise, and then writes:

“I love you with all of my heart, and I don’t want anybody else but you.”

That cruise never happened, and the couple didn’t reconcile.

Tyler and Shelley each went on to date other people and shared custody of their daughter, Lilli — until Shelley disappeared.

“That particular day she taught school, picked up Lilliana after school and picked up a box of Tyler’s belongings that she had found,” said Kevin Keele, a former cop who is now a legal investigator.

Keele worked the case for Shelley’s family for several years and is now consulting for CBS News.

“We know Shelley arrived at Tyler’s with Lilliana in a car seat,” he told Miller. “And by all accounts, we know Shelley was upset when she went into Tyler’s residence.”

What exactly happened after that is a mystery.

The next day, when she didn’t show up for work, Shelley’s mom called police. But it took a while for an investigation to get going and there wasn’t much to go on.

“I wouldn’t say no evidence, there’s no direct evidence. There is circumstantial evidence,” said Keele.

Remember that burning car? The one that firefighters rushed to in the middle of the night? 

It wasn’t long before police discovered who owned that car; it belonged to Shelley.

“It was arson,” Chief Farley said. “They had burnt the car intentionally. Most likely … it was to get rid of fingerprints or any kind of evidence that they might have left behind.”

And if covering up a crime was the goal of the arsonist, it apparently worked. There was no body in the car, no keys and no clues.

Shelley Mook was gone. The last person to see her was her ex-husband, and he was not being very cooperative.

THE INVESTIGATION

“When did you learn that Shelley was missing? Miller asked Brooks.

“It wasn’t till Wednesday after she went missing. I got a phone call,” she said.

“Where did your mind immediately go?” Miller asked.

“It immediately went to Tyler,” said Brooks.

Tyler Mook was the last person known to be seen with Shelley and he wasn’t being very cooperative. He wasn’t even helping with the search.

“You have to wonder if you’re not guilty, why are you not out searching with us? Why are you not helping us?” said Brooks.

“He never helped?” Miller asked.

“Nope. Not at all,” said Brooks.

You’d think the police would have been all over him.

“How did they handle this case as far as you’re concerned?” Miller asked Brooks.

“I feel that they dropped the ball in the beginning,” she replied. “It seemed like they thought that she possibly left on her own and they didn’t take our feelings seriously, our feelings of knowing that this was much more than they knew.”

“How did the police first proceed with this? Did they look at Tyler right away?” Miller asked Keele.

“I can’t speak to what they did initially, because that was before I became involved. I do know they were at his house searching with a mobile crime lab three days after she disappeared,” he replied.

Three days seems like a long time, but local police are not commenting, so we don’t know what happened. 

“How frustrated are you that there hasn’t been an arrest in this case?” Miller asked Keele.

“I am frustrated. To my knowledge, Tyler has not been interviewed about this case in depth at all,” he said.

“He hasn’t been interviewed by the police?”

“To my knowledge, he has not,” Keele replied.

Tyler Mook may not have been grilled by police, but Shelley’s family, fearing his involvement in her disappearance, took him directly to court — family court.

With Shelley gone, someone had to take care of Lilli and that was up to a judge.

Shelley’s family tried to use the custody case to get some answers about what happened to her.

But when Tyler was deposed, he was not forthcoming:

Attorney: What did you tell Lilli about her mother’s disappearance?

Tyler Mook: On advice of counsel, I respectfully decline to answer on the grounds of the Fifth Amendment.

Attorney: On February 28th, did Shelley come to your residence with Lilli?

Tyler Mook: On advice of counsel, I respectfully decline to answer on the grounds of the Fifth Amendment. 

Mook’s videotaped deposition 02:20

“In the deposition, he asserted his Fifth Amendment right against self-incrimination 140, 150 times plus,” said Keele.

“Is that normal?” Miller asked.

“Not if you’re innocent,” Keele replied.

Attorney: Did you have sex with Shelley on February 28th?

Tyler Mook:  Yes.

Attorney:  What time?

Tyler Mook:  On advice of counsel, I respectfully decline to answer on the grounds of the Fifth Amendment.

“So he refuses to answer that she came over to his house, that she came into his house, but he doesn’t have a problem answering ‘I had sex with her’?” Miller asked Keele.

“Correct,” he replied. “For whatever reason, he chose to answer that question during the deposition while refusing to answer numerous other questions.”

According to a transcript from another hearing in the custody case, Tyler Mook was more forthcoming.

He says that Shelley came over that afternoon and that they spent over an hour talking about problems in her life.

Mook said she broke down, crying over a boyfriend who may have been cheating on her. Then, he claims, they made love while their daughter, Lilli, was in another room.

Finally, Mook says Shelley left to do some errands, leaving Lilli and promising to be back before 10 p.m.

He says she never came back and he spent the entire evening with Lilli.

Mook says he texted and called Shelley, but only got one mysterious text message back from her around 7 p.m. It said: “i will babe.”

But there’s one other account of that afternoon. It comes from Shelley and Tyler’s 6-year-old daughter. A child specialist interviewed Lilli. 

“What did Lilli tell her?” Miller asked Keele.

“On the day her mother went missing, she and her mother went to Tyler’s house. Her mother got out of the car. She stayed in the car. Shelley went to the door, appeared upset, went inside, and that was the last time she saw her mother,” said Keele.

“She never saw her mother inside the house?” Miller asked.

“That’s correct,” Keele replied. “She was taken in the front door … and placed in her bedroom with the door closed, with instructions not to come out.”

It seems that only Tyler Mook knows exactly what happened in that house that afternoon.

But during the custody hearings, more allegations about Mook’s behavior before Shelley disappeared came out. And it didn’t look good.

Court documents say “numerous witnesses testified to the father’s history of illegal drug use, drug trafficking, violent behavior and verbal and physical abuse towards mother…”

“The red flag would have been probably the emotional abuse, the verbal abuse,” Brooks told Miller. “You know, just telling her that nobody would ever want her, or she wasn’t pretty enough.”  

“Would he do this in front of you?” Miller asked.

“He would do it in front of me, other family members, the physical abuse,” she replied. “He would grab her by the wrist … He’d, you know, push her against the wall.”

Asked if she was scared for Shelley, Brooks said, “Definitely. We all were scared for her.”

In the child custody case, the court ruled in favor of Shelley’s family. Her mother got primary custody of Lilli and moved her hundreds of miles away.

A year passed as Tyler and his family stewed about the court decision. The authorities seemed no closer to making an arrest in Shelley’s disappearance. Then, something really strange happened: 911 gets a call.

For lack of a better word, the caller had “butt-dialed” 911. He apparently did not know the 911 operator was listening to him and recording the call for 22 minutes.

The caller was Tyler Mook.

Tyler Mook:  You can’t take somebody’s kid away from ’em for the next 13 years, for something that I’ve never been charged with or something that somebody said.

The call is very difficult to hear, but Mook seems to be talking about that night — the night Shelley vanished and her car was burned:

Tyler Mook pocket dials 911 01:33

Tyler Mook:  They’ve already got a bunch of people lined up …  they already got people seeing me leave that night … Oh they’ve seen Shelley’s car going down that road that night … Oh someone seen me walking down the road in the middle of the night.

“He was in the garage with his father. They evidently were working with some power tools, probably had the phone in his back pocket and inadvertently leaned back and dialed 911 without meaning to,” Keele explained of the call.

“What was he worried about the car for?” Miller asked.

“I think he was worried that that there may be some evidence linking him to Shelley’s vehicle that was found burning around 12:30 a.m. on March first,” he replied.

At the end of the phone call, Tyler Mook suddenly realizes he must have accidentally called 911:

911: This is Robin. May I help you?

Tyler Mook: Yes, I was curious if my phone dialed 911? I looked down and it said it was on emergency call for the last 20 minutes.

911: OK. Yes, we had received a call from your phone …

Mook’s lawyer at the time told local media the whole 911 call meant nothing. It was simply Tyler talking about his painful custody battle.

“What does this 911 call say to you?” Miller asked Keele.

“In a nutshell, it proves nothing. But it certainly, when combined with all the other circumstantial evidence, would lead you to believe that he has some culpability,” he replied.

“What do you think his motive was?” Miller asked.

“Tyler seems to be the type of person that would have the mindset, ‘If I can’t have her, no one can,'” Keele replied. “I think he just snapped after learning that his ex-wife had spent the night with her boyfriend that previous night.”

Authorities have not commented about the 911 call and Tyler Mook has never publically spoken about the case.

“And what is the truth?” Miller asked.

“My personal belief is that Tyler was involved, and has knowledge of Shelley’s disappearance, the burning of her vehicle , and I believe he has knowledge of where she is now or her body may be,” Keele replied.

But years passed and there was nothing.

In spite of all the circumstantial evidence, without a body, authorities were not willing to move forward. The Tennessee Bureau of Investigation had named Tyler Mook a person of interest, but the case was stuck and Tyler moved away.

And then, Tyler got in trouble with a woman in Florida.

TROUBLED WATERS

It’s been six long years since Shelley Mook disappeared. Since then, Tyler Mook, her ex-husband, moved down to the warm Florida coast to start over. The case of his missing ex-wife, Shelley, has gone cold.

Until this story took an unexpected turn.

Tyler Mook had gotten himself into serious trouble. He attacked a woman in Florida on a boat.

“He grabbed my sunglasses off my head … And he … grabbed my bathing suit. It’s like he was gonna rip my bathing suit,” said Robin Doneth, Mook’s on-again, off-again girlfriend.

“And then finally, he picked me up and he threw me over the side of the boat,” she continued. “That’s when he jumped in behind me … turned me upside down and was holding me under. And I fought and fought just trying to find bottom, trying to find anything.”

The attack happened on Mook’s speedboat on the Intracoastal Waterway. Tyler and his brother, Andrew, and their girlfriends were out for some fun in the sun.

Doneth says she had been late to the party and that made Tyler mad. He was racing his boat through “go slow” zones, and when she started complaining, he got angrier.

“I just kept telling him ‘slow down,'” Doneth said. “I said, ‘you’re gonna hit a sand bar and kill us all.'”

Mook really lost his temper. He stopped the boat and threw her off, then he dived in on top of her.

“And I was just begging him, and just pleading him to please let me go. I just screamed, ‘Andrew, please help me,'” said Doneth.

Dylan Wedgewood and Juliano Garzia were out on a boat with friends, cruising down the Florida Intracoastal, when they came upon an unusual scene.

“She was screaming, ‘He’s trying to kill me. Help me. Let me on your boat…'” said Garzia.

“What did you see?” Michelle Miller asked.

“We saw two people in the water and she was just frantically splashing around,” Garzia replied.

“Should people be in this water? I mean it’s kind of murky. It’s dark. It’s — it’s a mess,” Miller pointed out.

“It’s just, it’s uncommon for you to be swimming up against the mangroves where you can’t get to shore if anything does happen,” Wedgewood explained. “And she was frantically splashing and swimming up to our boat.”

“We got her to the back of the boat, put down the ladder, and got her in right away.  And then he started freakin’ out and, like, yellin’.  And she was back here crying,” Wedgewood continued.

“He was freaking out at you two?” Miller asked.

“Kinda at everyone, yeah,” said Wedgewood.

“He just looked extremely pissed off,” Garzia added.

“He takes off around the other way and just goes back to the park,” Wedgewood said. “Probably full speed.”

“Floored it through the entire area,” said Garzia.

“And that’s a no-no?” Miller asked.

“Yeah that’s a no way,” said Wedgewood.

“It’s against the law,” said Garzia.

Wedgewood and Garzia took Doneth back to the dock. A police officer happened to be there.

When she told the cop Tyler Mook tried to drown her, he was arrested and eventually charged with attempted murder.

Robin Doneth and Tyler Mook

Surprisingly, Doneth says he wasn’t violent when they began dating.

“Very charming, like a perfect guy pretty much,” she said.

They were introduced by a friend and hit it off right away.

“‘Hi, I’m Tyler.’ And I said, ‘Hi, I’m Robin,'” she said. “And we were together every single day … He filled the void of a guy that I needed.”

But Doneth was curious about Tyler Mook, and after a couple months of dating, she Googled him.

“His ex-wife was missing, and he was the main person of interest. He was the last one to see her,” she said. “And he just said, ‘don’t believe anything that you see on the internet. None of it’s true’ …And he just pretty much told me that she was dating a guy overseas or something and he thinks that she just left and went overseas.”

Doneth says she was skeptical of Mook’s story and a little freaked out when she saw Shelley’s photograph.

“She resembled me — blond hair, around the same age, pretty,” she said.

Down in Florida, Doneth wasn’t the only woman who found Mook charming.

Erica Tucker and her fiancé met Mook through work and the couple ended up spending a lot of time with him.

“The one thing that impressed me about how Tyler treated me,” Tucker said. “The first question that he always had was regarding, ‘how are your children? How are the kids doing, Erica?’ And I always was thought that was very nice of him. “

One day, she too, found out he was suspected in the disappearance of his ex-wife.

“I said, ‘Tyler, like did you do that?'” said Tucker.

“You asked him that?” said Miller.

“I did, and he looked at me and he said, ‘No, I didn’t do that.’ He goes, ‘You know me, Erica. Do you think I would do something like that? I didn’t do that,'” Tucker replied.

Even Tucker’s friends seemed OK with Tyler.

“And so my best friend was coming over and she was like, ‘Erica, which one is the one that they think is, you know, the murderer?’ And I was like, ‘Tyler — the tall handsome one.’ And she’s like, ‘Get out! He was the nicest person here,'” she said.

“Let’s fast forward to the incident here in Florida,” said Miller.

“I was just scrolling through Facebook, and somebody shared a link. And I was like Holy Goodness! And I was like, ‘Honey, you got to see this. This is you know, Tyler was arrested for doing this,'” Tucker said.

“You knew they had a volatile relationship?” Miller asked Tucker.

“They would break up and get back together, break up and get back together and I knew that they would have arguments between them,” she replied.

“But when she claimed he tried to kill her, what was your reaction?” Miller pressed.

“I was shocked. I was shocked,” said Tucker.

But what shocked Erica Tucker more was the severity of the charges.

Tyler Mook stood accused of attempted murder.

THE TRIAL OF TYLER MOOK

“Those who were on the boat that day will tell you that the defendant picked up his girlfriend, Robin Doneth up, threw her into the water, jumped in after her — he held her under water,” Assistant State Attorney Kristen Chase addressed the court.

“They’re gonna try to establish that he had a conscious intent to kill,” Mook’s defense attorney, Arthur Marchetta, told jurors.

“They’re gonna try and establish that he had a premeditative design to effectuate the death of Robin Doneth,” he continued.

Two years after the incident, Tyler Mook goes on trial. 

“What happened that day in that water wasn’t a game. It wasn’t a splash in the water. The defendant attempted to murder Robin Doneth,” Chase told jurors.

“It’s our position that there’s just insufficient evidence to establish that under the facts of this case,” said Marchetta.

“The evidence will show you that the defendant is guilty as charged. Thank you,” said Chase.

Prosecutors were forbidden from telling the jury that Tyler Mook was a person of interest in his ex-wife’s disappearance, because under Florida state law, that critical piece of information was simply inadmissible in court.

“Did you two think someone was trying to kill her?” Miller asked the boaters.

“I think the way she was acting that somebody was definitely trying to hurt her or do something like that bad to her,” said Garzia.

“She seemed to be like in danger,” added Wedgewood.

Assistant State Attorney Nita Denton: How were you fighting him to get up?

Robin Doneth: Just tryin’ to push away from him and just tryin’ to get away from him with my hands.

Doneth says that after an outraged Tyler Mook threw her in the water, the terror continued:

Robin Doneth: He jumped in right behind me and grabbed me right away … He turned me facedown and he held me under the first time…

Defense attorney Marchetta: And then it happened again?

Robin Doneth: Yeah. I got up and I got one really quick gasp of air and then he pushed me right back under.

Defense attorney Marchetta: To the second time, did he spin you around?

Robin Doneth: No.

Victim’s emotional testimony 02:11

Defense attorney Marchetta: And you thought you were going to die at the hands of Tyler Mook, correct?

Robin Doneth: Yes.

Defense attorney Marchetta: So, when you got up the second time, you got away from him and you were able to start yelling for help, correct?

Robin Doneth: No, I was just begging him and pleading him just to let me go.

Under subpoena, Tyler’s own brother, Andrew Mook, is forced to testify against him:

Assistant State Attorney Denton: Would it be fair to say that you don’t want be here today?

Andrew Mook: That is correct.

As Tyler and Andrew’s anxious parents sit just a few feet away, Andrew says he witnessed Tyler throw Doneth overboard.

Assistant State Attorney Denton: Do you recall if she said anything when she came up?

Andrew Mook: She yelled for me … “he’s trying to kill me.”

Andrew Mook testifies 02:09

Responding to Doneth’s pleas for help, Andrew says he jumped into the water and wrestled Robin from Tyler’s arms:

Assistant State Attorney Denton:  What did you do towards your brother?

Andrew Mook: Put him in a chokehold.

Assistant State Attorney Denton: OK.  When you say you put him in a chokehold, using me, tell me what you did?  [Andrew demonstrates] OK.  And when you did that, what happened?

Andrew Mook: He let go of her, swam back to the boat.

Nicole Guajardo, Andrew Mook’s girlfriend, who watched this terrifying scene unfurl from the back seat of the boat, remembers Tyler’s chilling words:

“He looks at me and says, ‘no one disrespects me in front of my family. I’ll kill her,'” she testified.

Eyewitness testifies in Mook trial 01:22

“The evidence is not gonna suggest that he should win any awards for boyfriend of the month or get on the cover of Gentleman’s Quarterly. He was wrong,” said Marchetta.

 Mook’s defense attorney never put Tyler himself on the stand.  And he argued there’s just no evidence of attempted murder.

“When you hear what happened, it just doesn’t seem to make sense. Robin was able to yell for help, Robin was able to scream for the other boat,” Marchetta said. “She didn’t need mouth to mouth, she didn’t need to be resuscitated, she didn’t need CPR. She got back on the other boat.”

Tyler Mook Brenda Doneth

If Tyler Mook was guilty of anything, says his lawyer, it was of behaving badly.

“So he throws her in the water,” Marchetta told jurors. “It’s not as if he — he threw her into the rocks or threw her into the trees or into the mangroves. He threw her into the water, as if he’s throwing her into the pool…”

“Robin was drowning. Robin was fighting for her life. He doesn’t stop there either,” Chase addressed the court.

“What he did was moronic, what he did was probably wrong and rude. But not criminal. Not an attempt to kill. I’m asking you to find him not guilty. It’s not an attempt to kill,” Marchetta continued.

WHAT ABOUT SHELLEY?

Tyler Mook is found guilty of second-degree attempted murder and is sentenced to 12 years.

“I think I probably started crying a little bit, just happy I guess that he was convicted of what he deserved,” said Robin Doneth. “And just happy that he’s gonna stay away from me.”

With Mook in jail for a violent crime against his girlfriend, what will this mean for Shelley’s case back in Tennessee? 

D.A. wants justice 01:26

“How did you react to the news that Tyler had been arrested for attempting to kill his new girlfriend?” Miller asked Investigator Kevin Keele.

“Knowing what I did about Tyler’s violent temper, his controlling nature, didn’t surprise me,” he replied. “…what did surprise me is learning that Andrew stepped in and basically saved Ms. Doneth’s life.”

“Why did that surprise you?” Miller asked.

“Primarily because of the lack of involvement in locating Shelley and learning what happened to her up here,” said Keele.

“Do any of the family members hold the keys to this case?” Miller asked.

“All I can do I guess at that, but it would be hard for me to believe after listening to the 911 call … that no one had a clue what was going on,” said Keele.

911 RECORDING:

Jim Mook |Tyler’s father: They can’t prove nothing.

Tyler Mook: …and they know there’s a better chance of me leaving with Lilli, but like I told mom, they want to come arrest me with a warrant. All they got to do is arrest me.

Jim Mook: Someone is going to pay for this.

“Would it surprise you that his family would do anything to protect him?” Miller asked Brittany Brooks.

“No, absolutely not. I think his family would go to the end of the earth to protect him no matter what it took,” she replied.

Brittany Brooks stood up for her friend Shelley Mook, but throughout “48 Hours”‘ investigation — before and after Tyler Mook’s trial — we have reached out to Tyler, his family, and past and present lawyers.

CUSTODY DEPOSITION:

Attorney: You would lie for him to keep him out of penitentiary?

Jim Mook: No sir.

No one has been willing to defend Tyler — no one except his friend Erica Tucker.

“When you hear about everything in Tennessee, it’s scary and it’s very upsetting I think for everybody involved in this. However, I also know that he hasn’t been charged with anything regarding Shelley,” Tucker told Miller. “I decided in my heart that … I will never know the answer or the truth and I am not here to judge him.”

“Erica, his parents haven’t talked to us. His brother hasn’t, his brother’s girlfriend, no other friends. You’re the lone person who stands out and who is, in essence, defending his honor,” Miller noted. “What is it about him that has so struck you in a way that you see good in him?”

“I think what struck my heart the most is he has a daughter. And when Tyler would talk to me, he would talk to me … he would always talk to me and address me about my children.  And I remember that he had a lotta sadness that he never got to see his daughter,” Tucker explained. “…and I remember saying to him one time, ‘at least in the future even if you can’t see her now, one day you can show her that you’ve been trying to.'”

But Tyler Mook will have to keep trying.  Remember, a court in Tennessee had given custody of Lilli to Shelley’s family. Tyler’s family appealed that, but they lost.

The court said that Mook was “unfit to parent the child because of his history of domestic violence and the danger from exposure to the father’s drug activities…”

The court also slammed him for consistently taking the Fifth during his testimony.

The court wrote: “[o]rdinarily a party seeking custody of his child would testify of his love for his child, his activities for his child, and his plans… Well, in this case, the father did not testify for his love for Lily…”

Kevin Keele, right, pictured  with CBS News correspondent Michelle Miller, was hired by Shelley’s family to investigate her disappearance and is still on the case. CBS News

Meantime, Keele is not giving up. He’s working the case pro bono and hopes at least to find Shelley’s body.

 He took “48 Hours” to a cell tower in Beech Grove, Tenn.

“What is the significance of this particular cell tower?” Miller asked.

“This particular cell tower is the last tower that had any communication at all with Shelley’s cell phone on the day of her disappearance,” Keele explained of the tower where her phone last pinged.

“So, how would that have happened?” Miller asked.

“About 7:30 p.m. Now that was several hours after she was supposed to have last been seen,” said Keele.

“What would she be doing here?” Miller asked.

“That’s a good question,” Keele said. “I personally don’t think she was here, at least voluntarily.”

“Tyler has been convicted now of second-degree attempted murder,” Miller noted.

“It certainly makes the world a safer place for women, I think,” Keele said. “Robin Doneth got justice, Shelley has not.”

“And Lilli either,” said Miller.

“And Lilli either,” Keele affirmed.

Shelley and Lilli Mook Brittany Brooks

“I hate the thought of having that little girl grow up thinking, ‘my mother abandoned me. Did she not love me? Did she not want me? Why did she leave me? Why didn’t she say bye to me?’ Those are all valid questions that child has had to deal with and has dealt with every day since February 28, 2011, and I think she deserves some measure of closure and justice.

Tyler Mook remains a “person of interest” in the disappearance of his ex-wife.

Shelley and Tyler’s daughter, Lilli, still lives with Shelley’s mom.

HAVE INFORMATION?

Anyone with information is asked to call the Tennessee Bureau of Investigation at 1-800-TBI-FIND [1-800-824-3463].

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