"All of the agencies have been working diligently," says Yell County Sheriff Bill Gilkey.
After questioning the baby's mother, investigators got the answers needed to find the truck Brian and Harper Floyd rode in at one point, but the father and son were not inside.
Sheriff Gilkey says he's hopeful they're alive.
"I will say that after what I was able to view of the scene...I have a more positive feeling as far as an outcome of the situation," says the sheriff.
Sheriff Gilkey says as an avid outdoorsman, Brian Floyd could survive in the mountains, but they're concerned about baby Harper's safety.
"It is a dangerous place, but we're trying to feel confident in the father's abilities to survive in the woods," he says.
We don't know why Brian Floyd left with his son, but we do know, according to authorities, he has a history of mental illness.
Floyd's wife Brooke is being questioned in this case but the sheriff will not say if she's involved in any way.
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