Life jackets are designed to preserve life, yet in a tragic turn, they might just help unravel a mystery. These vests, found draped over 18-year-old Anna Kepner when she was discovered deceased on the Carnival Horizon cruise, could hold vital clues, according to an experienced detective involved in the investigation.

“The life jackets, along with the blankets and anything else retrieved from the room, including Anna’s remains, will undergo thorough testing,” explained Pat Diaz, a former homicide detective from Miami-Dade County, now working as a private investigator.

These items could potentially reveal significant information.

Anna Kepner’s lifeless body was discovered on November 7 aboard a Carnival cruise ship, where she had been vacationing with her family. (Anna Kepner/Instagram)

An initial investigation revealed signs suggesting Anna may have been suffocated through a chokehold, according to a report by ABC News on Friday.

A preliminary investigation found evidence Anna had been asphyxiated in a chokehold, ABC News reported Friday. 

Fox News Digital has not independently verified the report. An official cause and manner of death have not yet been determined, according to the medical examiner’s office. But a source with knowledge of the case said toxicology and other lab testing had not yet been completed but said bruises had been found on the body.

But if someone worked up a sweat during a murder, that person would have left DNA all over the room, the victim and anything used to cover the body, according to Diaz. 

As the FBI continues its investigation into Kepner’s mysterious death aboard a cruise ship, forensic experts are likely still analyzing DNA and other evidence for clues that could determine whether foul play was involved, experts say.

Anna Kepner was identified by her family as the passenger who died onboard the Carnival Horizon. (Instagram/Anna Kepner)

Friday marked two weeks since the aspiring Navy sailor was discovered dead in her cabin around 11 a.m. Nov. 7.

Her remains were transferred to the Miami-Dade County Medical Examiner’s Office after the vessel returned to port the following day. But the forensic pathologist in her case has not yet revealed a cause and manner of death.

Diaz said, at this point, it’s too early for results from toxicology and other lab testing. 

“Not only are they doing DNA to try and match the 16-year-old, they’re probably also trying to rule out the 14-year-old,” he told Fox News Digital. “And nothing’s happening fast because they’ll show what they get to a grand jury.”

Anna Kepner, her father, stepmother and several siblings in a family photo. (Shauntel Kepner/Facebook)

Kepner came from a large blended family with eight siblings.

No one has been charged with a crime in Kepner’s death, but her 16-year-old stepbrother’s parents have both said in court filings that he is being eyed as a “suspect” by the FBI.

The FBI declined to comment, citing the active investigation.

But others close to Anna have accused the 16-year-old of inappropriate behavior, ranging from climbing “on top of her” in the middle of the night as she slept to reportedly scaring her with a knife.

Her ex-boyfriend, speaking to reporters outside her memorial service Thursday night, said he was on a 3 a.m. FaceTime call with her when she fell asleep. Then, he claims, he caught her stepbrother slide into the frame.

Christopher Kepner (center, red hat) arrives at a memorial service for his daughter, Anna Kepner, at the Grove Church in Titusville, Fla., Thursday, Nov. 20, 2025. The 18 year-old cheerleader was reportedly found dead under a bed on a Carnival Cruise Nov. 7. (Mark Sims for Fox News Digital)

“I was like, ‘What the hell are you doing in her room?’” he said. “Then he got scared and ran away, and I heard his footsteps running through the house ’cause he got caught.”

If investigators are really eying him as a suspect as his parents suggested, they’re going to focus on the evidence in the cabin, Diaz said.

The stepsiblings were staying in the room together, Anna’s step-grandfather, Chris Donohue, told Fox News Digital previously.

“They’re not going to rush this one,” said Nicole Parker, a former Miami-based FBI agent who worked in the same office investigating Kepner’s death.

And they don’t need to, because if the juvenile is indeed the suspect, as his parents have claimed in court filings in a bitter custody battle, minors are less of a flight risk, Parker said.

“[Juveniles] can absolutely be charged, but the federal Bureau of Prisons, they can’t house minors,” she said. “So, if I’m gonna charge a juvenile, they have to be put in a special housing system. For that reason, sometimes the feds will give it to the locals.”

That’s unlikely in a case of this magnitude, however, she said.

“They could charge him federally, and they could potentially charge him as an adult,” she said.