The Long Island woman's remains were discovered in a Wyoming national park on Sunday, Sept. 19, eight days after her family reported her missing.
She had been traveling across the country in her van with her 23-year-old fiancé, Brian Laundrie, before her disappearance.
Laundrie returned to his parents' home alone in Petito's van, on Wednesday, Sept. 1.
Petito's stepfather, Jim Schmidt, said in an interview with Dr. Phil that was telecast on Wednesday, Oct. 6 that her body was found near remnants of a fire ring where a camp may have been set up.
Schmidt said he left a stone cross and flowers in the spot where she was found, the news outlet reported.
Laundrie has been named a person of interest in Petito's homicide, and authorities have been searching for him since his parents reported him missing on Friday, Sept. 17.
Petito's family called for Laundrie to turn himself in during the emotional interview.
The Laundrie family's attorney said Brian Laundrie's father is also planning to join law enforcement in the search for his son, according to the New York Post.
The FBI is asking people with information or sightings of Laundrie to call the agency at 1-800-CALL FBI or submit tips online here.
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