Brian Laundrie's looks will have altered since his last verified sighting, according to a top forensic artist.

Laundrie was last spotted on September 14 entering the huge Carlton Reserve in Florida, where he is a person of interest in the death of his fiancée Gabby Petito.

The FBI has filed an arrest warrant for the 23-year-old, and authorities are continuing their search for him, with TV stars like Dog the Bounty Hunter and former America's Most Wanted presenter John Walsh offering their help.

Lois Gibson, a forensic artist, has now stated that anyone looking for Laundrie should take in mind that his looks will have altered, whether purposefully or not. Gibson, who achieved a Guinness World Record in 2017 for assisting in the identification of 751 offenders and securing over 1,000 convictions, said on Newsnation's Banfield talk show that the stress of the scenario would have caused Laundrie's look to alter.

She knows what she is saying.

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She explained, "I've been working cases for 39 years and he is going to get a lot of sun, he's gonna lose weight. I don't care how much money he has. If you're on the run ... it's hard to eat, it degrades your life." The expert claimed that the least that Laundrie would do if he is smart and truly wants to evade the police would be to shave off his facial hair.

The search would not be a lost cause though even if Laundrie changes his appearance deliberately. The expert gave one tip: Look at the ears.This is the one telltale feature that often helped law enforcement identify and catch fugitives.

"Ears are the most complicated object on the surface of the head. They're more complicated than the eyes, lips or the nose," Gibson said.

More importantly, she added, "there's really nothing that can be done to alter them."

In the most recent update of the case, it can be assumed that the police truly needs all the help they can get. In a black SUV, two FBI agents came to the house with a huge brown paper bag.

They didn't take the same bag with them. One of the agents also climbed into a parked camper van for a few moments. The FBI came there, according to Steven Bertolino, the Laundrie family attorney, to gather anything that may aid them in their hunt for Brian.

"The FBI is at the Laundrie home today to collect some personal items belonging to Brian that will assist the canines in their search for Brian," he said. "There is nothing more to this."

The visit comes after a weeks-long hunt for Laundrie, whose parents said they last saw him on September 14 when he went to a local nature reserve. Gabby Petito, his fiancée, vanished late last month and was subsequently discovered dead near where the pair had last been seen together in Wyoming.

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