One morning, the family hears a loud ruckus; outside is their long-missing donkey accompanied by what the father identifies as an onager, a relative of the donkey family found in parts of Asia. The family is happy to see their donkey, named Grizzle. Grizzle is easily tempted by food the boys set out, but the onager is wary of humans. Eventually they tie a noose around her and secure her to their treehouse.

The next day, the father is determined to tame the onager and tries to do so as he has read cowboys in North America tame their horses. He jumps on the onager's back and seizes her ears, holding on for a very tumultuous ride. The onager finally gives in and allows the boys to ride her.

As the father senses the change in season, he begins to prepare for winter. Not certain what winter will bring, he notices the cloud cover growing thicker each day and the ocean waves becoming more stormy. He predicts that temperatures will cool down, even though the island is near the equator, and that the rains will be more prevalent.

To shelter his animals from the rains that will soon arrive, the father makes a roof over the vaulted roots of the family tree. This structure will serve as a stable, poultry yard, hay and provisions loft, and dairy. The family will share space with the animals, using the newly covered area as a kitchen and dining room. After the room is completed, the father directs his boys to fill the larder with provisions to last them through the colder months.

Foraging one day, they discover a field of broad grass, which the boys gather for various projects such as making whips. However, their mother is excited to recognize the grass as flax, from whose fibers linen is made. She orders her sons to bring as many leaves as they can harvest. Then she implores her husband to build her a spinning wheel. Over the next few days, they figure out how to extract the fibers from the leaves, and the father creates the best spinning wheel he can muster.

The rains begin. At first, the family enjoys having time for indoor activities. However, each member becomes restless as the rains never stop, giving them no chance to go outside without becoming completely soaked. The gray skies and torrential downpours make everyone a bit depressed.