Douglas is likely an alter ego for Ray Douglas Bradbury, the author. Bradbury claims in the introduction that much of the novel is based on his memories of growing up in Waukegan, Illinois, on which he bases the novel's Green Town. Over the course of the summer, Douglas experiences revelations and gains insights that force him to start growing up and thereby leaving some of the magic and innocence of childhood behind. Close with his brother, his father, and his grandfather, Douglas cherishes family and summer rituals.
Often shown in contrast to his older brother, Tom seems less inquisitive about the nuances of the world and the relationships within it. This lack of concern comes, perhaps, from his youth, for he hasn't yet had the same experiences. Nevertheless, Tom does confront his own brush with mortality when he worries about Douglas, both when Douglas is out late at night in the ravine and when he is stricken with a high fever. Although Tom seems more firmly entrenched in childhood, he, too, shows the beginnings of change.
Grandfather is kindhearted and enjoys the rituals of summer, such as making dandelion wine and mowing the lawn. He has passed along to Douglas his enthusiasm both for summer rituals and the importance of living at one with nature. Grandfather enjoys a close relationship with his grandsons not only because he is kind and patient but also because he retains a certain childlike wonder at nature and the joys it offers, so much so that Grandfather looks forward to mowing lawns and pulling weeds.
The children in Dandelion Wine see Colonel Freeleigh as a living, breathing time machine because he has the ability to transport the listener back in time with exquisite details about his experiences. He fought in the Civil War and is likely one of the last people alive to be able to recall what it was like. It's telling that his lesson is that no one ever wins a war and that he can't remember on which side he fought. Colonel Freeleigh demonstrates the importance of memory to one's identity, evidenced by his desire to call the places he's been to relive memories through sound.
Bill is portrayed as a wise soul but one who still has much to learn. He is eager to embrace progress, such as planting a new lawn that won't require mowing. Yet, he listens to Grandfather's advice to take solace in the slow pleasures. Bill also reveals that he once fell in love with a young photo of Helen Loomis, and the time they spend getting to know each other at the end of her life shows how suited their minds are for each other. Yet, they were born at the wrong time to be together, and soon Bill is left with only his memories of their time together.