One Rock at a Time

Rays of warm sunlight broke through the canopy of leaves above the trail ahead. "Daddy, I'm thirsty" the younger of the two children told his father. The trio took a moment's pause as the father dug in his son's pack for the water bottle the child refused to carry when they set out that morning. The sound of distant crunching of leaves and sticks caused the three to look down the trail. Two hikers approached, a middle-aged man and woman, both with carbon fiber hiking sticks in each hand.
"Good afternoon!" they called.
"Hello!" The older of the two children replied.
The two strangers waved and smiled as they passed by, and the sound of their footfalls and jabs of their hiking sticks striking dirt and rock faded as they disappeared behind the trees and foliage. The younger son downed a mouthful of water, and his father zipped up the pack on his back. The father glanced at the ground as he stood and froze momentarily. He calmly beckoned the boys to follow him, then once at a safe distance he drew their eyes to an orange brown lump less than a foot away from where the younger was just standing.
"Look boys, that's a copperhead." He said, as calmly as the small brook babbling near by. The older of the two children emitted a slight gasp, but his nerves were put at ease by the demeanor of his father. The snake was curled up in a puddle of sunlight that broke through the layers of leaves above, his brown and orange spots broken by bands of tan. They admired the serpent for a few minutes before continuing on the trail. Mid-day turned to afternoon, but the bright green leaves of spring provided ample shade over the forest floor and the hikers within.
"Dad, can we take a break?" The older brother asked.
Endurance is a virtue, but it wasn't one the eight year old had seemed to master yet, nor had his six year old brother. Four snack breaks had already come and gone. The father stepped from rock to rock, rock to root, stick to rock, and root to stick. The children quickly caught on to the game, careful to not touch the floor of dirt and leaves.
"Is it time to stop yet?" the younger asked.
"Not yet."
"When do we stop?"
"It's a secret!" the father replied. "Don't touch the ground! Just take it one rock at a time."

The elder brother sat on the bottom rack of a bunk bed. The mattress was covered with a green wool blanket, corners tightly tucked, the head-end edge covered by a portion of the taught top sheet, folded to four finger widths. His rifle hung from the corner post, and his boots sat atop a black footlocker that contained the few personal effects he was allowed to retain. He wore a green cotton shirt and green shorts, matching the nearly one hundred others around him. For the first time since he arrived on the island a week ago, he had time to unpack everything that had been crammed into his mind. He slid over to his footlocker, and after two attempts he finally opened the lock that secured it. From within, he retrieved a ball point pen, a small blue folder, a small roll of stamps, and a small book. Everything that actually belonged to him here seemed small and space efficient. There wasn't much room for himself, only the person he was supposed to become over the next three months. The din of the movement and shuffling of the others around him faded a bit as he took a small sheet of paper from the small blue folder and focused on what he was going to write. He penned a few words, paused, then a few more. After half a page or so, he put the paper down and picked up the small gray book. It was the only reading material he was allowed to bring. "Only 12 weeks to go" he thought. 12 weeks is a long time, especially given that he was barely a week in so far. After a few minutes of thumbing through the small bible, he noticed a small note on the inside cover:

One rock at a time.
- Dad