While speaking to protestors outside her house, Brian Laundrie's sister disclosed a deep family rift. Cassie and her husband Jim emerged from their privacy Monday night to speak to a crowd gathering outside her Lakeland Ranch front yard. Her parents' attorney has instructed them not to discuss Gabby Petito's death with anybody, including her.

It's the latest twist in a case that drew national attention after Brian Laundrie came home on a cross-country "van life" trip without Gabby Petito in early September.

The remains of the 22-year-old travel blogger were discovered in Wyoming's Bridger-Teton National Park on September 19. Petito died of homicide, according to preliminary autopsy results.

After being identified as a person of interest in the investigation, Brian Laundrie vanished. The FBI issued a warrant for his arrest on September 22 for allegedly exploiting someone else's debit card to make a cash transaction.

Per Inside Edition, Cassie responded, "I don't know," when asked if she felt her brother killed Petito. She also went on "Good Morning America" to say she last saw her brother on Labor Day at Fort De Soto Campground near Tampa.

Brian Laundrie's sister urges parents to help the police

Brian Laundrie's sister has asked her parents to "come clean" if they helped her brother following the death of his fiancee Gabby Petito. As the hunt for Brian goes on, Cassie Laundrie appealed to her parents to help the police, The Sun reported.

Brian Laundrie traveled back to Florida between August 17 and 23, according to Cassie, just days before Gabby was last seen on August 27. He was last seen on September 6, she said when his family went camping at Fort De Soto Park.

Brian disappeared from his parents' house on September 14 after informing them he was going hiking in the 24,000-acre Carlton nature reserve. Cassie asked Brian to "come out" and "help us out of this horrible mess" in her interview on Tuesday.

The fugitive is not a suspect in Gabby's death at this time, but he has been identified as a person of interest. On August 30, a warrant of arrest was released for misusing a debit card that did not belong to him.

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Parents changed statements on Brian Laundre's disappearance

According to Daily Mail, fugitive Brian Laundrie departed for a hike in Florida swampland a day earlier than his parents informed authorities.

He went on the evening of Tuesday, September 14 - two weeks after he returned alone from the ill-fated cross-country road trip with girlfriend Gabby Petito, 22 - according to his father Christopher, 62, and mother Roberta, 55.

However, Laundrie lawyer Steve Bertolino claims that the parents have changed their story and now claim that their son vanished on September 13. The Laundries did not report their son missing until the next week, on Thursday.

When Laundrie's silver Ford Mustang convertible was abandoned near his house in North Port, Florida, on Tuesday night, authorities claimed it was handed a police ticket at one of the entrances to the alligator-infested Carlton Reserve.

When asked what time Brian left the house on Monday, Bertolino remained silent. However, around 1 pm that day, Dailymail.com came to the Laundrie house to cover the news of Gabby's disappearance. Brian Laundrie had already vanished, as the Mustang was not in the driveway.

On the night of Saturday, September 11, officers arrived to the Laundrie residence to talk with Brian. Gabby's distressed mother, Nichole Schmidt, had reported her missing to her local sheriff's office near her home on Long Island, New York, just hours before.

The Laundrie parents, on the other hand, refused to "make Brian available" at the door, insisting that everything be handled through Bertolino. Brian was not seen by any cops at the house that night. "He was not seen," North Port police said.

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