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NORTH PORT, Fla. (WFLA) — Brian Laundrie’s father left the family’s North Port home for several hours on Thursday to help law enforcement in the search for his son, according to the family’s attorney.

Chris Laundrie walked out of his home around 10 a.m. ET with a plastic bag. He did not say anything to reporters or protesters outside the home as he got into his truck to leave. He then headed to the Carlton Reserve to assist law enforcement, the family’s attorney confirmed.

“Chris was asked to point out any favorite trails or spots that Brian may have used in the preserve,” he said. “Although Chris and Roberta Laundrie provided this information verbally three weeks ago, it is now thought that on-site assistance may be better.”

Chris Laundrie left the nature reserve around 1:45 p.m. to head home.

“There were no discoveries but the effort was helpful to all. It seems the water in the Preserve is receding and certain areas are more accessible to search,” Bertolino said. “The entire Laundrie family is grateful for the hard work of the dedicated members of law enforcement that have been searching the Preserve for Brian over the last few weeks. Hopefully Brian will be located soon.”

Former FBI Agent Dr. Bryanna Fox told us the participation from the parents is unusual. 8 On Your Side’s Mahsa Saeidi asked her why law enforcement would bring them to the scene.

“One is if they think that there’s something there that is very difficult to move, to have him identify it as perhaps being Brian Laundrie’s,” Dr. Fox explained. “It could be something like a tent or the manner in which he arranged his campsite.”

But more likely, Fox said, authorities may want to get the family alone and, over the course of a few hours, form a connection that could prove fruitful.

According to the attorney, Laundries parents “have been cooperating since the search began,” but noted that the nature reserve has been closed to the public – including the Laundries.

Bertolino said Wednesday night the father was supposed to join law enforcement in their search at Carlton Reserve on Wednesday.

According to Bertolino, “North Port police had to postpone Chris’ involvement” on Wednesday. However, when 8 On Your Side asked North Port police why, a spokesperson told us it wasn’t their department’s call.

“The FBI is the lead. The NPPD would not be making these decisions and actions,” Josh Taylor said. “The FBI would have to answer if that was true.”

Bertolino told WFLA that Brian’s parents, Chris and Roberta Laundrie, “are hopeful there will be another opportunity to assist.”

“Since the preserve has been closed to the public, Chris has not been able to look for Brian in the only place Chris and Roberta believe Brian may be,” he said.

(WFLA photo)

The search for Laundrie has been centered on the Carlton Reserve and is now in its third week. After several days of scaled-back activity, the search appeared to pick back up on Wednesday. Several unmarked law enforcement vehicles were seen at the nature reserve, and a large drone was spotted flying above.

Laundrie was officially reported missing by his parents on Friday, Sept. 17. At the time, they told police they had last seen him leave home to go to the Carlton Reserve area for a hike on Tuesday, Sept. 14. Bertolino confirmed earlier this week that, after further communication with the FBI, the Laundries now believe their son left home to go hiking on Sept. 13.

Laundrie was reported missing more than two weeks after police say he returned home to North Port alone from a cross-country trip he had been on with his fiancée Gabby Petito.

Petito was reported missing by her family on Sept. 11. From the beginning of that missing person investigation, Laundrie and his parents vowed to remain in the background. Petito’s family and law enforcement investigating the case had voiced their frustrations with the lack of cooperation and answers.

Laundrie was named a person of interest in Petito’s disappearance on Sept. 15, three days after his parents now say he left to go on a hike in the Carlton Reserve, and two days before he was reported missing.

Petito’s body was found in Wyoming on Sept. 19. A federal arrest warrant was issued for Laundrie on Sept. 23 following a federal grand jury indictment for use of unauthorized access devices after Petito’s death.

The FBI is still searching for Laundrie. His parents have not publicly spoken about his disappearance, nor the investigation into Petito’s death. However, his sister Cassie has spoken to protesters outside her home, as well as ABC’s Good Morning America.