NEW YORK – As the search continues for missing Long Island native Gabby Petito, the sister of her fiancé has spoken out, revealing she hasn't talked with her brother since he returned from the couple's cross-country van trip alone.
In an interview with "Good Morning America" that aired Friday, Brian Laundrie's sister, Cassie Laundrie, spoke about the extensive efforts to find Petito.
"Obviously me and my family want Gabby to be found safe," Cassie Laundrie said. "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."
She said she and her brother haven't spoken since he returned to his parent's house in Florida on Sept. 1 without Petito.
“I haven’t been able to talk to him. I wish I could talk with him,” she said.
“I’ve cooperated every way that I can. I wish I had information where I would give more,” she said. “This is all I have… this I gave to the police.”
She described her brother as a "wonderful" uncle to her children who has always done the right thing.
“He’s always been there when I need him,” she said. “He’s been there every time Gabby’s needed him.”
His sister also commented on the bodycam video released Thursday showing police in Moab, Utah, responding to a report of a domestic violence incident involving the couple on Aug. 12, about two weeks before Petito went missing. Petito and Laundrie were ultimately separated for the night, and no charges were filed against Petito, who police determined was the aggressor.
During the incident, Laundrie told police that the couple's months-long travels had created an "emotional strain" and "increased the number of arguments" between them, according to a police report.
“It looked typical of both of them,” Laundrie's sister said of the bodycam video. “Whenever they’d fight, they’d take a little break and come back and be fine. Because that's what you do in a couple.”

Speaking to NewsNation’s Ashleigh Banfield in an interview late Thursday, Petito’s father, Joe Petito, responded to an excerpt of Cassie Laundrie's interview, criticizing what he called the Laundrie family's "version of love."
“It actually made a lot of sense. It brings things to light,” Petito said of the sister's remarks. “Because we’ve been looking for Gabby for how long? And they’ve known that Brian’s been there since (Sept.) 1st. I mean that was a very nice, well-written statement. But it does explain if that’s that family’s version of love, to just ignore and not care that someone’s gone and people are looking for them and the entire country’s looking for them. I mean that explains how we got to where we are today. Because, I mean, look at their version of what they call love.”
Earlier Thursday, the Petito family's attorney delivered a letter to the parents of Brian Laundrie.
"We are writing this letter to ask you to help find our daughter," said Richard Stafford, an attorney for the Petito family, who spoke on their behalf Thursday. "We understand you are going through a difficult time and your instinct is strong to protect your son. We ask you to put yourself in our shoes."
Petito's parents said in their letter that their lives are "falling apart," pleading for the Laundries' help to locate their daughter who disappeared in late August.
"We believe you know the location of 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? ... she's going to be your daughter-in-law."
"All we want is Gabby to come home," the family added. "Please help us make that happen."
Stafford said the Petito family is devastated by their daughter's disappearance and are desperate for answers.
"They're at the point that that desperation is turning to anger," he said. "They know that the Laundries' know where their daughter is and they will not tell them. That's infuriating."

Asked at a press conference in Florida earlier if any criminality was suspected in the case, North Port Police Chief Todd Garrison said, “None at this time.”
“Right now, it’s a missing person case,” he said.
Petito, 22, and fiancé Brian Laundrie, 23, started their trip in a Ford Transit van back in July from Long Island, where they both grew up, according to their social media accounts. They intended to reach Oregon by Halloween, but Petito disappeared after her last known contact with family in late August from Wyoming’s Grand Teton National Park, authorities said.
Laundrie drove the van back to Florida on Sept. 1 alone, police said. Petito's family filed a missing persons report last Saturday with police in Suffolk County. On Wednesday, Laundrie was named a “person of interest” in the case by North Port police; he has not been charged but is also not cooperating, despite pleas from Petito’s family.
Asked by a reporter Thursday if Laundrie could be “brought in” by police for not cooperating or driving Petito's van to Florida, Garrison said, “No.”
“Our focus is to find Gabby,” the police chief said. “My focus isn’t to bring Brian in right now. It’s to find Gabby. Brian is exercising his constitutional rights, and I have to respect that. But as of right now, the focus is finding Gabby.”
“We share the frustration of the world right now,” Garrison said of the fact Laundrie hasn't spoken with police. “Two people went on a trip, one person returned. And that person that returned isn’t providing us any information.”

Garrison said investigators are concentrating on Wyoming, where Petito was believed to have last been.
“Right now, that seems to be the area that we’re looking at,” he said, adding that authorities are still trying to narrow down an area to physically search as they continue to analyze and vet information and leads.
“We have no physical search teams on the ground, like doing grid search right now,” Garrison said. “We have resources and law enforcement partners that are out in the field following tips and leads, but as far as a grid search right now, we’re still trying to narrow down geographical areas.”
Petito’s father, Joe Petito, spoke at Thursday’s press conference, saying, “What I need from everybody here is help, because the goal is still not met, and that goal is to bring Gabby home safe.”
“I’m asking for help from everyone at home. I’m asking for help from the parents of Brian. And I’m asking for help of the family members and friends of the Laundrie family, as well,” Petito said.
“Whatever you can do to make sure my daughter comes home, I’m asking for that help,” he said. “There’s nothing else that matters to me now.”
Petito urged people to contact a national tip line set up by the FBI if they have information. The number is 1-800-CALLFBI (225-5324).
The Associated Press contributed to this report.
