What's "strange" about the scene where they found Laundrie's remains?
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(CNN) -
The discovery of Brian Laundrie's remains ends a manhunt that had gripped the country for weeks as investigators searched a Florida nature preserve for the 23-year-old, who returned home last month from a road trip without his fiancée, Gabby Petito.
Petito spent the summer traveling the American West with Laundrie, sharing his travels on social media.
The case first attracted widespread attention after Petito's family reported him missing on September 11.
The chronology of the disappearance of Brian Laundrie does not close: these are the discrepancies between the authorities and his family's lawyer
Laundrie would soon disappear from her parents' home in North Port, Florida, just days before Petito's remains were found in a national forest in Wyoming.
Investigators had been focused on locating Laundrie ever since, until Wednesday, when they finally found him.
They confirm that remains found are of Brian Laundrie 1:51
But there are still many things that we do not know.
Here's what experts say about their deaths:
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How did Laundrie die?
Dental records confirmed the remains found this week to be Brian Laundrie, the FBI announced Thursday.
But determining the cause of death could be challenging, as authorities recovered "skeletal remains," said Jim Clemente, a retired FBI profiler.
He added that Laundrie may have been dead the entire time he was missing.
"It doesn't necessarily mean that," Clemente told CNN's Erin Burnett on Thursday.
"But what it does mean is that it will be much more difficult to make a good, solid determination about the cause and manner of death."
"Unless there is some type of major and serious trauma to the skull that can be identified, there may not be a way to determine how he died," he said.
"If he drowned, for example, there would be no evidence of that in a skeleton."
The remains were found in an area of the Carlton Reserve - a vast nature reserve of more than 10,000 hectares - that had previously been underwater but recently dried up due to the weather.
Police tape restricts access to the Myakkahatchee Creek Environmental Park on October 20, 2021 in North Port, Florida.
Criminal defense attorney Mark O'Mara said the most reasonable explanation is that Laundrie took his own life in the nature preserve, a possibility that Steven Bertolino, Laundrie's parents' attorney, addressed Friday in an interview with "Good Morning America "from ABC.
Laundrie's attorney and parents had discussed the possibility of Laundrie dying by suicide "multiple times," the attorney said.
"We just don't know. Of course, knowing his state of mind when he walked out the door was always a concern," said Bertolino, who had described Laundrie in other interviews as "heartbroken."
Bertolino told GMA that the family would accept the coroner's decision if they offer another explanation for the cause of death.
Forensic pathologist Dr. Priya Banerjee agreed that investigators face a challenge in determining the cause of Laundrie's death.
However, researchers could use a notebook found near Laundrie's remains to get an idea of how he died.
"Maybe the diary or other evidence can shed some light on what happened," Banerjee said.
What happened in the time you were missing?
It is unclear how Laundrie spent his time on the reservation or when exactly he died.
For a month, investigators kept their eyes on the Carlton Reservation, where Laundrie was believed to have gone when she left her parents' home in the days after Petito's family reported her missing.
Brian Laundrie: From a trip across the country with Gabby Petito to the confirmation of her death.
Chronology of the case
The search through the reservation began on September 18, the day after Laundrie's parents filed and reported Brian missing, stating that he had left the house days earlier and had not returned.
But the search turned out to be difficult, with researchers working in extreme conditions.
They were bogged down by the elements, wading through high water and trying to avoid dangerous wildlife.
Conditions were so bad that survival experts were skeptical of Laundrie's ability to survive, telling CNN weeks ago that he was probably no longer alive or on reserve.
North Port police officers block the entrance to the Myakkahatchee Creek Environmental Park on Wednesday, Oct. 20, 2021, in North Port, Florida.
There are also questions about when Laundrie left her parents' home and when police learned her whereabouts were unknown.
The Laundrie family originally told police that he left home on Tuesday, September 14, but later changed his account and indicated that he had left the day before.
Bertolino told CNN's Chris Cuomo on Wednesday that he notified the FBI that Brian had not returned from a hike at Carlton Reserve the same day he left.
The FBI did not comment on the report, but North Port police spokesman Josh Taylor said his agency was not notified.
Laundrie did not return from the hike until September 17.
He said in a statement that police believed he was at home until that day, when the parents agreed to speak with the police.
Regardless of when Laundrie left her parents' home, Taylor on Thursday rejected the idea that the belongings found on the reservation may have been recently planted, indicating that they had been there for some time.
Why didn't the Laundries speak to the police earlier?
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What happened to Gabby Petito?
The main of the questions that have not yet received an answer are about what happened to Petito.
What we do know is this:
The remains found Sept. 19 in the Bridger-Teton National Forest in Wyoming were identified as Petito's, according to the FBI.
The manner of death was ruled a homicide by Teton County Coroner Brent Blue, who said the cause of death was strangulation.
He likely died about three to four weeks before his remains were found, he said.
Gabby Petito's cause of death was strangulation, coroner says
But no other details of the autopsy will be released, according to Wyoming law.
Some details of Petito's death are still shrouded in mystery: When did he die and what led to his murder?
While the FBI described Laundrie as a "person of interest" in Petito's murder, he did not face charges in his death.
However, he was charged with allegedly using two financial accounts that did not belong to him in the days after his murder.
A vehicle travels in the Bridger-Teton National Forest, east of Grand Teton National Park in Wyoming, on Sunday, Sept. 19, 2021.
Once again, experts noted that the notebook found near Laundrie's remains is a potential key to answering these questions.
"In terms of understanding Laundrie's motive, his feelings for Petito, maybe even any kind of notes or comments he made about the events that we are still trying to understand in Wyoming, that notebook could shed a lot of light on those issues," said former FBI Deputy Director Andrew McCabe.
Clemente, the retired FBI profiler, echoed those comments, telling CNN: "If that notebook contained, for example, information that could have been admissions, it could be projecting blame or rationalization; all that information could help in the determination".
A notebook found near Brian Laundrie's remains could answer some key questions, experts say
It is not clear if the laptop will be useful.
It was clearly wet when authorities found it outside a dry bag during their search Wednesday, a source with knowledge of the investigation told CNN, describing it as "possibly recoverable."
"They are going to use any potential means to dry it before opening it," the source said.
"They will be very careful with that."
The focus has also been on Laundrie's parents and whether their son told them anything about what happened to Petito before he disappeared.
Petito's family had pleaded with the Laundries to cooperate with authorities after reporting Gabby's disappearance.
When police showed up at Laundrie's home on Sept. 11, requesting to speak to Laundrie and his family, the Laundries directed their attorney to authorities, Taylor said.
On Friday, Bertolino told GMA that his clients had been cooperating with the FBI since the "first day" of Brian's disappearance, but said they had "absolutely nothing to say" about Petito.
When asked in an interview if Laundrie said anything to his parents about Petito before going to the reservation last month, Bertolino said: "It is not something I can comment on at this time. I would like to leave it at that."
Brian Laundrie Case: Why is the notebook that was found important?
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CNN's Christina Maxouris, Amir Vera, Eric Levenson, Kristina Sgueglia and Randi Kaye contributed to this report.
Brian Laundrie Gabby Petito
