Who visits while Brent is making the whirligig?

This question must refer to the seventh chapter, called “Apprentices.” While Brent is building his third whirligig near a beach in Tampa, Florida, some children become interested in what he’s doing. They had been playing on the beach when they suddenly become aware of Brent and his workspace. They interfere more than they help, though. They ask him lots of questions. Someone grabs and plays his harmonica. Suddenly Brent feels “like a substitute kindergarten teacher.” He doesn’t have extra wood for them to experiment with, but he does have extra nails. He sets the children up with a hammer and some nails. This activity appeases them for a bit. Then they run off to the beach again. Making this marching band whirligig is a two-day job for Brent. The children don’t show up on the second day. He can finish his work in peace.