New critical details about the involvement of Brian Laundrie's parents in the killing of Gabby Petito emerged.

Months after the case seemingly quieted down, new details about the tragic murder came into the limelight again.

CBS News shared the amendment to the lawsuit filed by Petito's parents. It now alleges that, during their search to find the YouTuber, Laundrie's parents knew their son killed Petito and where her body was left behind.

It adds that, while Petito's family was distraught as they attempted to find her, Laundrie family chose to go on a vacation at Fort De Soto Park in Florida.

"Christopher Laundrie and Roberta Laundrie exhibited extreme and outrageous conduct which constitutes behavior, under the circumstances, which goes beyond all possible bounds of decency and is regarded as shocking, atrocious, and utterly intolerable in a civilized community," the filing said, as quoted by PEOPLE.

The Petito family is now asking for an additional $30,000 from Chris and Roberta Laundrie as they suffered mental anguish due to their intentional deceitful actions.

Gabby Petito's Family Continues To Seek Justice

The late YouTuber's parents first filed the lawsuit in March. They claimed that Laundrie's parents helped the fugitive cover-up Petito's murder while refusing to provide more information to the police.

"Christopher Laundrie and Roberta Laundrie knew of the mental suffering and anguish of Joseph Petito and Nichole Schmidt, and knew that they could alleviate, at least in part, such mental suffering and anguish by disclosing what they knew about the well-being and the location of the remains of Gabrielle Petito, yet they repeatedly refused to do so," the lawsuit said.

Before Petito's body was recovered, the Laundrie family still managed to release a statement, expressed their hope for the search to be successful.

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Due to Chris and Roberta's potential connection to the crime, Petito's family now sees the past statement as something beyond outrageous.

In response to the new amendment, the Laundrie family's attorney Steven Bertolino told CNN that they are confident the case would soon be dismissed. It reportedly does not give them rise to liability.

The 22-year-old woman died by strangulation following a cross-country trip with Laundrie. Two weeks after embarking on their journey, she suddenly disappeared.

Laundrie was also found dead in a Florida reserve, with a medical examiner ruling his cause of death as suicide. A notebook in which he admitted to killing his fiancée was also found.

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