In late August, Gabrielle, who goes by Gabby, lost contact with her family. Before that, the 22-year-old was believed to be in Grand Teton National Park in Wyoming on a cross-country van road trip with Brian, 23, police in North Port, Fla. said in a statement. On Sept. 1, he returned to the town, where he and Gabby lived in a home with his parents. Her own parents reported her missing on Sept. 11 and police say Brian is a "person of interest in this case" and "has not made himself available to be interviewed by investigators or has provided any helpful details."
"I haven't been able to talk to him. I wish I could talk to him," Brian's sister Cassie Laundrie told ABC's Good Morning America on Friday, Sept. 17. "I've cooperated every way that I can. I wish I had information or I would give more."
Cassie also said, "Me and my family want Gabby to be found safe. She's like a sister and my children love her and all I want is for her to come home safe and sound and this to be just a big misunderstanding."
A day earlier, Richard Stafford, a lawyer for Gabby's parents, Joe Petito and Nichole Schmidt, and her stepparents, Tara Petito and Jim Schmidt, read at a press conference a letter addressed to Brian's parents, Christopher Laundrie and Roberta Laundrie.
"We understand you are going through a difficult time and your instinct to protect your son is strong," Gabby's parents and stepparents wrote, according to NBC News. "We ask you to put yourselves in our shoes. We haven't been able to sleep or eat and our lives are falling apart. We believe you know the location where Brian left Gabby. We beg you to tell us. As a parent how could you let us go through this pain and not help us. As a parent how could you put Gabby's younger brothers and sisters through this."
The letter continued, "Gabby lived with you for over a year. She was going to be your daughter in law. How can you keep your location hidden? You were both at Jim and Nichole's house. You were both so happy that Brian and Gabby got engaged and were planning to spend their lives together. Please, if you or your family has any decency left, please tell us where Gabby is located. Tell us if we are even looking in the right place. All we want is Gabby to come home. Please help us make that happen."
The FBI has gotten involved in the investigation, led by the North Port police. No arrest warrants have been issued. Meanwhile, an attorney for Brian's family, Steven P. Bertolino, said in a statement on Wednesday, Sept. 15 that Brian will not speak on the matter because "intimate partners are often the first person law enforcement focuses their attention on in cases like this and the warning that 'any statement made will be used against you' is true, regardless of whether my client had anything to do with Ms. Petito's disappearance."
"I have been informed that the North Port, Florida police have named Brian Laundrie as a 'person of interest' in this matter," Bertolino said, according to NBC News. "This formality has not really changed the circumstances of Mr. Laundrie being the focus and attention of law enforcement and Mr. Laundrie will continue to remain silent on the advice of counsel."
North Port Police Chief Todd Garrison said in a statement that day, "We are pleading with anyone, including Brian, to share information with us on her whereabouts in the past few weeks. The lack of information from Brian is hindering this investigation."
On Tuesday, Sept. 14, Brian's parents said in a statement released by their attorney that this is "understandably an extremely difficult time for both the Petito family and the Laundrie family."
"It is our understanding that a search has been organized for Miss Petito in or near Grand Teton National Park in Wyoming," the family said, according to NBC News. "On behalf of the Laundrie family it is our hope that the search for Miss Petito is successful and that Miss Petito is reunited with her family."
Gabby and Brian had documented their travels on YouTube. On Aug. 19, more than a week before she last had contact with her family, they posted a video titled "Beginning Our Van Life Journey," which showed them kissing, running on a beach, camping and driving in a white 2012 Ford Transit van. North Port police said in a statement that the vehicle, owned by Gabby, was recovered at the home she shared with Brian and his parents on Sept. 11 and that the van was "was fully processed for evidence along with FBI agents Tuesday evening."
Meanwhile, on Thursday, police in Moab, Utah released a bodycam video showing cops responding to a 911 call about a suspected domestic incident involving Gabby and Brian on Aug. 12, during which she tearfully talks about an argument between them that turned physical.
"We've just been fighting this morning," she said. "Some personal issues."
The police report, obtained by NBC News, noted that Brian "tried to create distance by telling [Gabby] to take a walk to calm down, she didn't want to be separated from [him], and began slapping him. He grabbed her face and pushed her back as she pressed upon him and the van."
The incident appeared to be more a mental and emotional "break" than a domestic incident, authorities said, and the police report stated that the couple also "reported they are in love and engaged to be married and desperately didn't wish to see anyone charged with a crime," NBC News reported. No arrests were made.
At a press conference on Thursday, Garrison commented on the video, saying, "Yes, they had a disturbance, yes, it was captured on a body camera—their interaction with law enforcement—but beyond that, I don't know what it has to do with the disappearance."
(E! and NBC News are part of the NBCUniversal family.)
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