The Fayetteville Police Department and the Federal Bureau of Investigation said they need the public's help to build a timeline of when Blake and London were last seen.
According to investigators, the Deven family moved to Fayetteville in 2015. In November 2016, they moved to a home in the 1800 block of Eichelberger Drive where they lived until June 2019.
The family then moved to the 1400 block of Berridale Drive and has been there since.
Investigators ask anyone who visited, delivered to, purchased from, or sold something to the addresses to call authorities. Anyone who repaired something or saw something at the homes is also asked to call.
London Deven was last seen in 2019 in Fayetteville. Blake Deven was last seen in 2022 at a Walmart on Ramsey Street.
On April 12, police said they found partial skeletal remains that the state's chief medical examiner's office is testing. Police wouldn't say where the remains were found but noted they were not found at the home on Berridale Drive.
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Officials said the family who currently lives at the home on Eichelberger Drive is not connected to the investigation and are cooperating.
John Whitaker lives in the same neighborhood where the Deven's live on Berridale Drive. He said he has seen police in the neighborhood repeatedly.
"I don't think these kids are alive. I don't think so. I don't think so...because it's too long," Whitaker said.
He said he didn't feel like cops were searching urgently enough or were trying to solve the case quickly.
"The percentages aren't with them in my opinion," he told ABC11.
Anyone with information is asked to call the Fayetteville Police Department at (910)-578-2697 or the FBI at (800) CALL FBI or online at tips.fbi.gov.
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