UPDATE May 16, 2019:

The lawyer for Justin DiPietro said his client is not responsible for the death of Ayla Reynolds in response to the wrongful death lawsuit filed against DiPietro back in December 2018, WMTW-TV reports.

The official response was filed in court on Thursday, May 16, 2019.

"He doesn't believe a child could have left on his own," Michael Waxman, the lawyer for DiPietro, said. "He believes some adult must have taken her."

His lawyer also said he and his client are prepared for the lawsuit to go to trial. DiPietro would have to take the stand.

FULL STORY: Lawyer for Ayla Reynolds' father responds to wrongful death lawsuit - WMTW

UPDATE December 17, 2018:

Trista Reynolds and her attorney, William Childs, filed a wrongful death lawsuit alleging Justin DiPietro caused Ayla’s death, and said at a news conference that they hope depositions related to the suit will help solve the case, Boston.com reports.

Sworn testimony from DiPietro and others who were in the house, who could potentially be served subpoenas, could help shed light on exactly what happened that night. Reynolds said she hopes it builds groundwork for eventual criminal charges.

MORE: 20-month-old Ayla Reynolds disappeared 7 years ago. Now her mother is suing her father - Boston.com

UPDATE Dec. 15, 2017:

In a Crime Watch Daily exclusive, the father of Ayla Reynolds, breaks his silence about what he says happened the day she vanished -- and what he thinks really happened to her.

UPDATE Sept. 27, 2017: Ayla Reynolds, missing since December 2011, was officially declared deceased Wednesday.

Bangor Daily News reports: "Missing Waterville toddler Ayla Reynolds, the focal point of the largest criminal investigation in Maine State Police history, has officially been declared deceased by a Cumberland County probate judge.

"Ayla Bell Reynolds died on or about December 17, 2011, Judge Joseph Mazziotti officially declared, according to documents filed Wednesday," Bangor Daily News reports.

CWD: Missing: What happened to Baby Ayla Reynolds?

May 23, 2016:

It's one of the most publicized cases ever in the state of Maine. A darling little 20-month-old is reported missing by her father.

Ayla's father says he put his child to bed, but in the morning she was gone. Is she simply just missing, or did something else happen inside that house? The answer to that question depends on who you ask.

Trista Reynolds wants answers. But what she desperately needs is her baby daughter Ayla.

Twenty-month-old Ayla Reynolds mysteriously disappeared from her own father's house in Waterville, Maine just days before Christmas 2011. Police discover a disturbing amount of blood. It's Ayla's, but she's nowhere to be found.

Little Ayla was a surprise pregnancy for Trista and her then-boyfriend Justin DiPietro.

"He said let's put her up for adoption," said Trista. "I said 'You're absolutely crazy, I will not do that.'"

Trista was a loving mom, but shortly after Ayla's first birthday, an old demon surfaced. She made the decision to go to rehab.

"I needed to get myself better for her, that's why I did it," said Trista.

The plan was for little Ayla to stay with Trista's sister, but Trista says Justin and his mom pulled a fast one and convinced a Department of Health and Human Services worker to give them legal custody.

But shortly after Trista checked into rehab, she claims Justin and his mom, Phoebe DiPietro convinced a Department of Heath and Human Services worker they were supposed to have legal custody of Ayla.

Trista and her father Ronald Reynolds were both worried about Ayla living with Justin. They both claim she often came back home with mysterious injuries, which is consistent with what DHHS found in its investigation.

"She had bruises like going up her leg, and I said 'What's this, Justin?' And he was like 'Oh, she was playing at Chuck E. Cheese in a ball pit and some little kid was kicking her,'" said Trista. "Problem was there was no ball pit at Chuck E. Cheese."

Trista immediately checked herself out of rehab and began to fight to get Ayla back.

"I said 'Justin, why aren't you bringing her to me? Why won't you let me see her?'" said Trista. "And he said 'You're never going to see her again.' And that's when I started thinking 'What are you doing?'"

Trista says Justin kept Ayla from her for weeks, and then she learned her daughter had a broken arm. Justin claims it was raining and dark, he was carrying her, he tripped on some steps and accidentally landed on top of little Ayla. But Ronald says it was an all-too-familiar story.

"I don't believe it was an accident," said Ronald, Trista's father.

Trista says she called to check on Ayla, but Justin told her their 19-month-old daughter is too busy to come to the phone.

"He said 'Well, she's watching 'Home Alone' right now,' and I was like 'Really, you're not going to let me talk to her?' and he never did, and that was it," said Trista.

Trista would never speak to or see her daughter Ayla ever again.

"I got on the phone, and it was my dad, and he was in tears, and I said 'Dad, what's going on, what's wrong?' And he said 'The police are here and Ayla's missing. Nobody knows where she is,'" said Trista.

According to the Maine State Police, Justin put Ayla in her bed around 8 o'clock the night before, and when he went to check on her the next morning her bed was empty.

"Obviously when a toddler wanders off, we obviously start searching, starting from the place where she was last seen, and in this place it was their home, and that search got wider and wider," said Steve McCausland, a spokesman for the Maine Department of Public Safety.

While police and divers searched every inch of Waterville, investigators begin questioning Justin, his sister Elisha, and his girlfriend Courtney, who were all in the house that night. All three claim little Ayla was abducted.

"We don't think she was abducted, we don't think she wandered off, and we think foul play is involved," said McCausland.

Within days, what began as a desperate search for a lost little girl turns into a hunt for a possible killer.

"We think it is highly unlikely Ayla Reynolds will be found alive," police announced at a news conference.

Police found Ayla's blood throughout the house.

Trista says police showed her crime scene photos from inside the house the morning Ayla went missing, and a map pinpointing every spot where they found Ayla's blood.

"It was found on her slippers, a baby doll, in her car seat, but I feel like the downstairs is where it all ended for Ayla because of what they found, and they also found vomit and saliva mixed in with her blood," said Trista.

Then, Trista says, cops gave her their theory of what happened to Ayla.

"They actually think that it ended with them rolling her up in a blanket and sticking her in a tote," said Trista.

Police refuse to name anyone a suspect. But they wholeheartedly believe there's a dirty secret being covered up.

"We have said from the very beginning that the three adults inside that home know more than they have told us," said DPS spokesman Steve McCausland.

For months Justin, his girlfriend and sister refuse to talk, then Trista is tipped off: Justin has a court date for an alleged domestic battery incident.

She shows up to confront him once and for all.

A heartbroken mother's frustration erupts outside of a Maine courthouse. Trista Reynolds desperately wants answers from one of the last people to see her baby daughter Ayla alive: Justin DiPietro, Ayla's dad.

But he's not talking.

Justin's mother, Phoebe DiPietro, even turned the tables:

"I'm Aylas's grandmother and I believe she's alive," she said.

She has said that it was Trista who took Ayla.

After four agonizing years without her daughter Trista is left chasing the truth as to what really happened inside DiPietro's house in Waterville, Maine.

Justin DiPietro, his sister Elisha, and his then-girlfriend Courtney Roberts were all in the house the night 20-month-old Ayla disappeared. They all claim they had nothing to do with the toddler's disappearance, and insist she was kidnapped from her bed by a stranger.

But Maine State Police are adamant this was no abduction.

"We thought foul play was involved, likely from the very start," said Maine Dept. of Public Safety Spokesman Steve McCausland.

They say there's plenty of evidence, and it all leads them to one sad conclusion: little Ayla is dead.

The only thing investigators will tell us about the evidence found inside the house is that they did in fact find blood. It was in the basement and the DNA matched Ayla.

Police still won't name a suspect, but Ayla's grandfather, Ronald Reynolds, says he's confident Ayla was murdered, and in several published reports he claims the motive was money.

"Three days before she went missing he took out an insurance policy out on her," said Ronald Reynolds. "$10,000."

Trista says on the days leading up to her daughter's disappearance there were ominous signs: little Ayla's arm was broken in what Justin called an accident. And a number of news outlets have reported Justin DiPietro began sending disturbing text messages Trista.

"He said 'You're never going to see her again.' I feel like those were messages like giving me warning," said Trista.

"As much as he could be mean, I don't think that he planned to kill our daughter, I don't. I don't," said Trista. "I think that things got really out of hand, and I think that he didn't know how to handle it the way that he should."

But Justin maintains his innocence. In fact, he told a local newspaper he took a polygraph test, and "I smoked it."

"The only answer truthful answer that you could say about that is 'I told the truth I passed my polygraph,'" said Peter Hyatt. "Instead he said 'I smoked it,' as if it was a junior-high math test that he got past. This was a child that went missing."

Peter Hyatt is a statement analyst, a sort of human lie detector who helps police with cold cases.

"Ayla's case touched me emotionally through the news, but it was the initial statement that the father had made that got my attention," said Hyatt.

"One of the first things he said, he referenced her in the past tense," said Hyatt. "This is not something that a parent of a missing child will do. Referencing someone in the past tense is an indication of knowledge or belief that the child is dead."

We asked Peter to analyze some of Justin's statements.

"He spoke briefly with 'The Today Show' in 2012 and said 'I would never do anything to harm my daughter and she's the world to me.' This statement has no commit. He did not say 'I did not harm my child.' He said 'I would not,' and there's a difference there."

Peter says the most telling statement may be in that heated confrontation in front of the courthouse between Trista and Justin's mom Phoebe.

"What she did was confronts Trista, 'What did you do with Ayla,' but turns away knowing there's no answer to that," said Hyatt. "What we saw with Phoebe was a bullying of Trista Reynolds."

Justin has never been named a suspect, but Ayla's mother Trista, and police, are convinced he knows more than he's saying.

Trista is so desperate for answers she's even tried tracking Justin down on the street.

Trista hasn't been able to get anything out of Justin. So I went back to the house where little Ayla disappeared. Justin, his mom Phoebe and his sister Elisha still live here. Justin wasn't home but his sister Elisha, who was also in the house that terrible night, was. She asked me not to show her face on camera but agreed to answer a few of my questions.

"On the record, I will say that we do believe she is out there somewhere," Elisha said.

Did investigators show you evidence from what they had from what was found inside the house?

"We have seen pictures of what they found, yes," said Elisha.

What would explain the blood?

"She had been vomiting quite a lot. She had lactose issues. So she had been sick," said Elisha. "Nothing happened in the house that night."

No foul play?

"No foul play in the house that night," said Elisha. "My brother is a good father, he loved his daughter. Still loves her."

And there is a little boy who loves, misses and even dreams of the day Ayla is found: Her little brother.

"My 5-year-old tells me that he plays with her in his dreams and she's got these beautiful wings, and they're always playing in a garden with these other people with wings," said Trista. "He tells me right there, that's she's in heaven, that she's looking down and she's watching us."

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