Although e-books allow young children to read independently, children could be missing out on opportunities to develop positive emotional associations with reading. The current study explored whether there are differences in emotions and physiological arousal when parents and children read traditional books or e-books together or when children listen to e-books alone. Seventy-four 4-year-old children were randomly assigned to read the same storybook in one of three conditions: reading a traditional book with parent, reading an e-book with parent, or listening to an e-book independently. Parents and children wore Electrodermal Activity (EDA) sensors to measure skin conductivity, an index of sympathetic arousal. Reading interactions were videotaped and coded with a microanalytic coding system to capture children’s and parents’ emotional expressions. Children had more peaks in arousal and were coded as happier and more interested when reading the e-book and the traditional book with their parents than when listening to the e-book alone. Neither children nor parents demonstrated differences in arousal or emotional expressions between the e-book and the traditional book conditions. These findings suggest that the format of the book is not as crucial as reading with a parent and imply that children can have positive experiences around e-books. E-books, when used with an adult, can prompt the same types of positive interactions as traditional books.