Gabby Petito's family has called on Brian Laundrie to turn himself in as they spoke for the first time since their daughter's death.
Petito's stepfather Jim Schmidt, father Joe Petito and mother Nichole Schmidt thanked law enforcement and people around the world for their support and helping find Gabby's body.
Each family member showed off new tattoos, which they said were designed by Petito.
The tattoos read "Let it Be" and "Believe."
When asked about the Laundrie family's silence, Gabby's father rolled his eyes.
The family's lawyer Richard Stafford was scathing in condemning Brian's parents Chris and Roberta Laundire for their lack of co-operation.
"The Laundries did not help us find Gabby. They are sure not going to help us find Brian." He said the family had one message for Brian Laundie.
"We are asking you to turn yourself in," he said bluntly.
The family said they trust the FBI to get justice for Gabby.
"The Petito parents are 100 per cent with the FBI. They've been with us every step of the way. We know they will bring justice for the family," Stafford said.
During the press conference, the family announced they would be starting a non-profit titled the "Gabby Petito Foundation" in honour of their daughter.
The press conference was held just one day after the family of Petito's fiancé, Brian Laundrie, affirmed they do not know his whereabouts two weeks after he was last seen, their lawyer said in a statement on Monday night.
"Chris and Roberta Laundrie do not know where Brian is. They are concerned about Brian and hope the FBI can locate him," lawyer Steven Bertolino said. "The speculation by the public and some in the press that the parents assisted Brian in leaving the family home or in avoiding arrest on a warrant that was issued after Brian had already been missing for several days is just wrong."
The Petito family has not spoken since the funeral of their daughter was held on Sunday afternoon.
Hundreds of mourners on Long Island in New York stood in a line that wrapped around the block to attend a public memorial service for Petito on Sunday.
Petito was reported missing by her parents on September 11 after she did not respond to calls and texts for several days while she and her 23-year-old fiance were on a cross-country camping trip.
After the missing persons report was filed, police discovered Laundrie had returned to his parents home in North Port, Florida, alone in the van on September 1. He later became a person of interest after he refused to co-operate with investigators.
On September 17, Laundrie's parents told investigators they had not seen their son since September 14.
At Petito's funeral her father, Joseph, told a crowd gathered that the day was about remembering his daughter, not relishing in the sadness of her death.
"When you leave here today, be inspired by what she brought to the table because the entire planet knows this woman's name now. And she's inspired a lot of women and a lot of men to do what's best for them first," he said. "I couldn't be more proud as a father."
Petito appeared to offer his thoughts on Laundrie as he spoke to those gathered.
"If there is a trip you want to take — do it now while you have the time," he said. "If there is a relationship that might not be the best for you — leave it now."
Her stepfather, Jim Schmidt, offered a positive message: "It's okay to mourn for Gabby, and it's okay to feel sorrow and pain. But we want to celebrate her and how she lived her life."
Schmidt said his stepdaughter was an "example for us all" as she adventured and enjoyed "every moment of this beautiful world."
The services were held in Holbrook, New York, near the Bayport-Blue Point community where Petito grew up and became the high school sweetheart of Brian Laundrie before the couple moved to Florida.
Laundrie was last seen 12 days ago when he told his parents he was going hiking in the Carlton Reserve, a sprawling wilderness area and wetland near his home in North Port. Authorities have been searching the reserve area for more than a week.
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