"We have the potential to still bring him home," he said.
But it's an investigation that has so far failed to answer a heartbreaking question: What happened to Kyron Horman?
Terri Horman said she last saw him walking to his classroom after the two of them had attended a pre-school science fair together.
The school said he never made it to class, but he was not reported missing until the end of the day, when he did not get off the school bus that was supposed to bring him home.
Kyron's disappearance triggered the biggest search in Oregon history.
"We are not in a position to talk about suspects," Multnomah County Sheriff's Office Capt. Jason Gates said.
Kyron's biological mother, Desiree Horman, has insisted that her son "is still alive," but she also implied that Terri Horman knows more than she is telling.
"We implore Terri Horman to fully cooperate with the investigators to bring Kyron home," she said Thursday.
That is exactly what Terri Horman has been doing, though, Staton said on Friday.
"To date there has been no indication through our detectives or through our investigators that she's been uncooperative," Staton said at a news conference that was called because of the flood of media questions his office has received about the case.
Meanwhile, people have left cards and balloons at the fence outside Kyron's school, all expressing wishes for his safe return.