(CNN) -- Four-year-old Jacob Spillers was trapped in mud so thick it was like freshly poured concrete.
But the little trouper didn't panic as rescuers worked to free him from the mudslide that had swallowed most of his house and trapped his father and some other family members Saturday.
"He didn't cry. He didn't move. He just stood there and was a very composed little man," Ed Hrivnak, a volunteer pilot for the Snohomish County Helicopter Rescue Team, told CNN on Tuesday.
Jacob was upstairs when the mudslide swept through the house. His father and three half-siblings have yet to be found.
Randy Fay, a helicopter rescue team coordinator for Snohomish County, on Wednesday recalled spotting the boy "out in the middle of nowhere" not long after his crew first flew over the scene Saturday.
"We have no clue how he ended up there by himself," Fay said. "(There were) no homes, no nothing."
Jacob's dramatic rescue was recorded by a camera on the Snohomish rescue team's helicopter. It was an uneasy save. The helicopter couldn't set down on the uneven, sticky soil so it hovered a few feet above the ground. The rotors sucked up debris, chopping up insulation and spitting it all over the scene.
Two men who lived nearby saw the child; one managed to get to him, but no one could get any traction in what Fay described as "a mushy slurry (that) once you got into it, there was no way to push yourself up."
By the time rescuers got to the boy, his pants had fallen to around his ankles. They came off entirely "when we pulled him out of the mud," Fay remembered.
That left the boy "shivering badly" wearing only his underwear and a sleeveless T-shirt, according to Fay. But at least he could get warm, and at least he was safe.
And he was calm as he was passed up into the arms of crew chief Beau Beckner.
"That little guy was very brave," Beckner wrote on the rescue team's Facebook page.
Another woman rescued that Saturday, Robin Youngblood, recalled talking to the boy and cradling him in a blanket.
"I said, 'Honey I'm a grandma, I'll take care of you until we figure this out,'" she told CNN's Anderson Cooper on Wednesday. "... I sang him songs, and I just tried to help him stay calm."
Jacob's mother, Jonielle Spillers, is safe. She was at work during Saturday's mudslide, which killed at least 16 people and destroyed much of two towns north of Seattle. Another eight bodies have been found but not recovered, officials said. As of Wednesday, a county official said that 90 people were officially missing or unaccounted for.