The next morning he was missing.

One of Dad's range riders picked up Dan several miles to the north, walking along, whistling gayly.

The next morning he was missing again and was caught still farther away.

After that Dad had a terrible scene with him--I don't know exactly what happened--but Dan promised to run away no more, and ever since then Dad has been closer to Dan than anyone else.
"So Dan grew up.

From the time I could first distinctly remember, he was very gentle and good-natured, but he was different, always.