This article argues that the costs children incur during treatment for cancer should be rendered visible. As economic agents, children expend time, engage in productive work and participate in activities. Each of these aspects of daily life can be affected by cancer and/or its therapy and can be considered costs of illness. This article challenges researchers to consider eliciting children's views and assessments of these costs to illustrate more fully the impact of cancer on children and their childhoods. The resulting findings will provide a more accurate account of the social and economic costs incurred by families over the course of children's treatment trajectories. Ultimately, such information could be used to lobby for changes which would improve the life circumstances of children and their families.