Billy Lally, the youngest of the Bedwetters, suffers from a strong sense of insecurity. His parents, despite their wealth, find little opportunity to give him the attention he craves. To somehow escape his profound loneliness, Billy develops imaginary friends called "Ooms" who inhabit his parents' sauna. Despite these problems, Billy demonstrates a natural comfort and ease with animals, contrary to his brother, who often acts cruelly toward them; when the group leads the buffalo over the fields, Lally two speaks softly to the buffaloes and establishes a profound connection with them. Billy is perhaps the most dynamic character in the novel. At the end of the novel he becomes willing to leave behind the pillow he has cherished as an item representative of his sense of security. In addition, while he remains exceedingly passive during the first part of the book, when the Bedwetters attempt their rescue mission, he volunteers to scale an intimidating catwalk.