Tommy and Timmy Tibble also known as the Tibble Twins are twin boys at D.W.'s age, four, who routinely exasperate Arthur, D.W., and mostly everyone with their destructive antics. Although they are a little reckless, they are sweet and kind twins. In an early episode in the first season, the characters at D.W.'s preschool were the mischievous Billy and Bobby. Tommy wears a red scarf and Timmy wears a blue scarf. They repent for many of their mistakes and live with their kind, but weary, grandmother.