In an interview with CNN, John Walsh said he doesn't think the 23-year-old was ever in the Florida wildlife preserve where authorities have been searching for him.
His parents reported on Friday, Sept. 17 that they hadn't seen their son since Tuesday, Sept. 14.
The FBI named Laundrie a person of interest in the homicide of Petito, age 22, who was from Blue Point in Suffolk County. The couple had been traveling across the country in Petito's van before her disappearance.
Laundrie returned home to North Port, in Sarasota County, Florida on Wednesday, Sept. 1 without Petito and did not cooperate with investigators after Petito's family reported her missing on Saturday, Sept. 11.
Petito's remains were discovered in a Wyoming national park on Sunday, Sept. 19.
In the interview with CNN, Walsh was critical of the statement from Laundrie's parents that they found their son's car at the large Florida wildlife preserve they said he had visited.
"My philosophy is he never went to the swamp," Walsh said. "His parents and the lawyer on the phone bought him four days to get out in front of this."
Walsh also questioned whether anyone has seen any proof that Laundrie was in the home when his lawyer had previously said he was.
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