BRIAN Laundrie displayed numerous red flags in his relationship with Gabby Petito - which surfaced as the couple traveled cross-country together.
The 22-year-old’s death was caused by manual strangulation and Laundrie is the only current person of interest in the vlogger’s homicide.
The case gripped the nation as private investigators, psychologists, forensic experts, and online sleuths have flagged a number of red flags in Laundrie's behavior since he vanished on September 13.
One of the last times Gabby was seen alive involved a row with Laundrie at a Wyoming restaurant called Merry Piglets.
Dr Ann Wolbert Burgess, who pioneered the FBI's Behavioral Science Unit, told Fox News the argument between fugitive Laundrie and Petito that witnesses observed at a Wyoming restaurant on August 27 may be the key to Petito's tragic fate.
She said: "How she has to apologize for his behavior is something that's kind of characteristic, and this probably enrages him even more because he wants to appear in a certain way.”
Describing the argument that took place on August 27, a witness Nina Celie Angelo told ABC News: "It looked as though they were like almost getting kicked out.
"It wasn't necessarily between them, it was more so Gabby abruptly leaving the restaurant crying, and Brian was just evidently really upset, p***ed off, I would say.
"I would say Gabby was upset, he was angry, and he was just being very temperamental towards the restaurant staff."
Angelo described Laundrie's body language as "aggressive" and said that he left and returned to the restaurant around four times, continuing the conflict.
At one stage, Gabby came inside and apologized for Laundrie’s behavior, Angelo alleged.
Read our Brian Laundrie live blog for the very latest news and updates...
Dr Burgess said the argument happened "on the day or very close to the day that she is murdered".
The forensic nurse said the other significant incident, indicative of serious problems in their relationship and danger in Laundrie's actions, was the domestic dispute police responded to 15 days earlier on August 12 in Moab, Utah.
It has not been confirmed whether Laundrie is on drugs or not but the fugitive revealed to Moab cops that he suffers from an anxiety disorder, for which he does not take his prescribed medication.
Sleuths have trawled through the 23-year-old's Pinterest page and found what they claim are pictures of LSD tabs decorated with characters from the cartoon Adventure Time.
They also claim Laundrie's posts give insight into his mental state with a folder named "Bleak" containing morbid imagery.
Social media users have questioned the couple's drug use in a Reddit subthread where a forensic psychologist answered questions about Gabby's case.
When asked whether drug use could have played a role in Gabby's death, a forensic psychologist verified by the site claimed that it would "depend on how much and how frequently he was using drugs."
Hand-drawn images Laundrie created and posted to social media have caught the internet’s attention.
His “demonic artwork” features blood, knives and violence. Dr. Orna Guralnik, a psychologist from New York, exclusively told The Sun that “sociopaths will act on violent images.”
One such post, dated July 8, 2020, shows what appears to be a man wearing a wolf mask, sat in a chair and holding a blood-soaked knife, with red splatters up his arms and legs.
Behind the subject's head is a red circle, with three other animal mask-wearing figures holding guns and a bat.
A second image, captioned "Grim Reaper leading sheep to the slaughter", shows a herd of sheep surrounded by ghoulish figures wielding scythes.
Some of the reapers have been carved into mousetraps and outlined in red.
Another artwork, which Laundrie says was crafted with pen and watercolor, shows Frankenstein's monster chained to a chair made of rock and wood.
In the image, which is in black and white, the monster has shackles around his ankles, feet, and neck.
A fourth work, this time in blacklight form, shows a red skeleton, with its arms in the air and mouth agape, looking up as red splatters - resembling blood - surround it.
Dr. Guralnik exclusively revealed to The Sun that the couple showed signs of S&M dynamics in their interaction with Moab police, which is common in abusive relationships.
The couple showed tendencies of sadomasochistic dynamics, which when one person enjoys inflicting physical or mental suffering on another person.
Guralnik said, “In this dynamic, one becomes more abusive and the other becomes passive and docile.
“The bond in those cases can be very, very strong.
“It’s like they’re locked in a certain kind of spell state between them and there are lots of cases of domestic abuse that follow that pattern.”
She proceeds to describe S&M as a pattern that makes it very hard for two individuals to separate as they are in a “fierce, perverse bond.”
Bodycam footage revealed that Gabby and Laundrie were immediately separated and questioned by cops.
Guralnik said the couple “clearly didn’t want to have the cops help them disentangle from each other.
“They wanted to continue, none of them said ‘please get me out of here.’
“They were locked into this kind of spell.”
Brian Laundrie timeline
Brian Laundrie has not been seen since the morning of September 13. Here is a timeline of Laundrie's latest whereabouts:
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