Cheerleader’s Brother Finds Her Dead in Bed — Leading to Discovery of Her Secret Relationship with an Older Teen

Fourteen-year-old Tristan Dilley seemed to have everything to look forward to.

The vivacious teen was a freshman at Silsbee High School in Silsbee, Texas, and a valued member of their cheerleading squad. She participated in the school’s first homecoming prep rally late last month and, on Saturday night, attended a school dance and sleepover at a friend’s house.

But on Sunday, authorities say, Tristan’s 13-year-old brother found her dead in her second-floor bedroom at her mother’s home in Buna, Texas. She had been shot twice in the head with a .22-caliber magnum revolver.

Her brother found her body, fully clothed, on top of the bed. She wasn’t facing her killer.

“She never saw it coming,” Jasper County, Texas, Sheriff’s Lt. Ryan Cunningham tells PEOPLE. “You could tell from the scene there was not a struggle or a fight. She was comfortable with knowing the person.”

As investigators would come to discover, Tristan’s killer, an older teen, was someone with whom she was connected — though their romantic relationship remained partially secret from both families.

And at the end of their hunt for a suspect, authorities instead found a suicide with several lingering questions.

The Case Is Cracked

Lt. Cunningham, who worked alongside Jasper County Sheriff Mitch Newman and Lts. Scotty Duncan, Jason McClelland and Cal Morgan, says detectives quickly ruled out a break-in in connection with Tristan’s death.

“She was very positive,” Silsbee High School Principal Paul Trevino tells PEOPLE. “She had that type of personality that people wanted to be around her and hang out with her.”

Investigators learned that Tristan had been dating a boy named “Adam” — but none of her family or her fellow cheerleaders knew much about him, other than his name and what they believed was his age: 16 years old.

Her dad told authorities that Adam was “tall and lanky” and “supposed to be a high school basketball player,” Cunningham says.

School records and officials were no more successful in locating the teen’s boyfriend, but investigators caught a break when they began searching through her phone and Facebook activity.

Some of the messages between Tristan and the other boy seemed to indicate a pattern of clandestine meetings — coordinated around when her mother would and wouldn’t be home — Cunningham says.

The records also pointed to the true identity of her boyfriend: Paul Audrey Adams, a 19-year-old nursing student at Lamar State College.

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“I called dispatch and had them start pinging his cellphone,” Cunningham says. “We put out a BOLO out for him in the surrounding area. We were able to get a general location of the cellphone and we learned of his address,” in nearby Vidor, Texas.

Authorities arrived there about 1:30 a.m. on Monday, but he wasn’t home. His mother said he’d left the afternoon before, about 3:30, to meet “some girl in Beaumont he met at school,” Cunningham says.

“Both kids were deceiving the parents,” he says. “He knew he was too old to be seeing the child.”

Police searched his room and found a spent .22-caliber magazine casing lying in the middle of his bedroom floor.

“We don’t know if it was from something previous, but we knew it was probably the type of round used Tristan,” Cunningham says. “We don’t know if maybe that it was a trophy type thing. Sometimes they keep memories.”

A Grisly End to the Search

At 10:30 a.m. Monday detectives got a call from a Texas Ranger who told them he had gone back to interview Adams’ mother and was talking to her when Adams called her, Cunningham says.

“The Ranger listened for a few minutes and took the phone,” he says. “He tried to get Paul to come in and speak to us, but he didn’t want to come in.”

Cunningham alleges that, in that phone conversation, Adams admitted to the Ranger that he had been over at Tristan’s house the day she died when they heard an intruder coming upstairs.

“He gave a description of an older white male with a beard,” Cunningham says. “He said he hid in the shower and he could here Tristan screaming, ‘Get off of me.’

“He said he heard two gunshots and heard the man running out of the house. He waited a couple of minutes and then found Tristan dead and he didn’t know what else to do so he ran.”

After Adams told the Ranger this story, the Ranger then “heard a distinct gunshot and he believed Paul had shot himself,” Cunningham says.

He says they started searching for Adams when, around noon on Monday, they came upon a tent and Adam’s white ’94 Toyota next to a canal just east of Vidor.

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They were about 150 yards away and approaching further when they saw Adams reach for his gun.

“As soon as me and my partner said, ‘I think he has a gun,’ we observed the suspect shoot himself in the head and collapse,” Cunningham says.

At the scene, authorities discovered a suicide note reiterating Adams’ claims of innocence — which Cunningham says is disproved by the evidence.

“It was basically verbatim what he told the Ranger,” Cunningham says. “In the letter he said there was nothing he could do to change what happened to her and going to prison wouldn’t be worth it. He said, ‘I know people are going to think I did this.’ ”

But Cunningham says detectives learned that a few days before Tristan’s killing, Adams had bought an axe, a machete, a hatchet, several knives, 32 meal rations, cases of water, burlap saps, dumbbells and duck tape. He had also purchased several sets of handcuffs and chains.

“It was a premeditated event,” Cunningham says.

Detectives also discovered that Adams had downloaded apps from his phone and had been listening to police dispatch traffic as they investigated Tristan’s death, according to Cunningham.

“I think he knew we were coming,” he says, “but I don’t think he realized it was going to be quite so fast.”

With his story of a violent intruder, Cunningham says, Adams was just trying to cast blame elsewhere: “Why would you not immediately notify law enforcement? Why would you run and go to the extent of buying all of these items? It was pretty clear cut. You could read between the lines.”

Still, even with what they now know, a motive in the slaying remains elusive.

“It was senseless, and it makes no sense,” Cunningham says. “There are so many questions we can’t answer. We will never know what was going on in his mind and what was said between them.”