The letter was read by the family's attorney, Richard Stafford, on Long Island, where both Petito and Laundrie are originally from despite having lived in Florida for the past two years with Laundrie's parents.
So far, the Laundries have not aided the investigation, citing advice from legal counsel, which authorities say is hindering the investigation.
RELATED | PD: Missing woman's boyfriend a person of interest, hindering search
The letter reads as follows:
Christopher and Roberta Laundrie,
We are writing this letter to ask you to help find our beautiful daughter. We understand you are going through a difficult time and your instinct to protect your son is strong. We ask you to put yourselves in our shoes. We haven't been able to sleep or eat and our lives are falling apart.
We believe you know the location 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.
Gabby lived with you for over a year. She was going to be your daughter in law. How can you keep her location hidden? You were both at Jim and Nichole's house. You were both so happy that Brian and Gabby got engaged and were planning to spend their lives together. Please, if you or your family has any decency left, please tell us where Gabby is located. Tell us if we are even looking in the right place.
All we want is Gabby to come home. Please help us make that happen.
Brian Laundrie has been named a person of interest in the case, and the letter comes on the same day police in Utah released body camera footage of officers' encounter with the couple on August 12.
The video released by the Moab Police Department shows that an officer pulled over the van after it was seen speeding and hit a curb near the entrance to Arches National Park. The body camera video shows Petito visibly upset when an officer approached them.
"We've just been fighting this morning, some personal issues," she tells him, adding that she suffers from obsessive-compulsive disorder that affects her behavior. "Yeah, I don't know, it's just some days, I have really bad OCD, and I was just cleaning and straightening up and I was apologizing to him saying that I'm so mean because sometimes I have OCD and get frustrated."
WATCH THE FULL BODY CAM VIDEO:
Laundrie says on the video the couple got into a minor scuffle that began when he climbed into the van with dirty feet, and said he didn't want to pursue a domestic violence charge against Petito, who officers decided was the aggressor.
"I'm not going to pursue anything because she is my fiancée and I love her," Laundrie says. "It was just a squabble. Sorry it had to get so public."
Ultimately Moab police decided not file any charges and instead separated the couple for the night, with Laundrie checking into a motel and Petito remaining with the converted sleeper van.
"He's going to a hotel," an officer says. "I'm giving you the keys to the van. I'm giving him a ride to the hotel. Everything will be OK."
Laundrie drove the Ford Transit van back to Florida on September 1 alone, police said. Petito's family filed a missing persons report last Saturday with Suffolk County police.
RELATED | Gabby Petito disappearance timeline: What we know so far
Laundrie's attorney, Steven Bertolino, said the Laundrie family is hoping for Petito's safe return, but he's asked them not to speak with investigators.
Petito is described as a white female, approximately 5-foot-5 and 110 pounds.
She has blonde hair, blue eyes, and several tattoos, including one on her finger and one on her forearm that reads "Let it be."
Detectives are asking anyone with information on Petito's disappearance to contact Suffolk County police at 1-800-220-TIPS, the North Port Police Department at 941-429-7382, or the FBI at 1-800-CALL-FBI.
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