NORTH PORT, Fla. (NewsNation Now) — Gabby Petito’s family said they want “vengeance and justice” in their daughter’s death and called on her boyfriend Brian Laundrie to turn himself in.

“We want vengeance and justice and for him to pay for his crimes and to spend it in a prison for the rest of his life,” Gabby Petito’s stepdad James Schmidt said in an interview with “60 Minutes Australia.”

Laundrie has not been charged in Petito’s death, but authorities say he is a person of interest in the case.

Petito vanished while on a cross-country road trip with Laundrie in a converted camper van. The trip was well-documented on social media until it abruptly ceased, allegedly somewhere in Wyoming.

Petito, 22, was reported missing Sept. 11 by her parents after she did not respond to calls and texts for several days. Petito’s body was found Sept. 19 just outside Grand Teton National Park in Wyoming. A Teton County Coroner said last week that Petito died by strangulation three to four weeks before her body was found.

It has been weeks since any firm new details emerged in the case as authorities search for Petito’s boyfriend. Brian Laundrie’s parents say they last saw him Sept. 13 when they said he took the car to a 24,000-acre Florida reserve. He was reported missing Sept. 17.

Schmidt says the family wants to reframe the way people are talking about Laundrie, saying he is no longer missing but is in hiding.

“Can we change missing to hiding? Gabby was missing,” said Schmidt. “There’s a lot of other people out there that are missing. He’s hiding. We were up every day and every night until we found Gabby. Are the people that love him doing the same thing for him? And why not? Because if they were, maybe it would be found by now.”

Police have been searching for nearly a month in a Florida reserve, but have not found Laundrie or said if they have found clues.

“Gabby Petito’s death at such a young age is a tragedy,” the Laundrie family attorney, Steven Bertolino, said in a statement to NewsNation last week. “While Brian Laundrie is currently charged with the unauthorized use of a debit card belonging to Gabby, Brian is only considered a person of interest in relation to Gabby Petito’s demise. At this time Brian is still missing and when he is located we will address the pending fraud charge against him.”

The FBI has issued an arrest warrant for Laundrie. He is wanted for “use of unauthorized access device” related to his activities following Petito’s death. The FBI says he used a debit card and a PIN to access two bank accounts Aug. 30 and Sept. 1.

The Associated Press contributed to this report.