Several studies have suggested there is a developmental link between executive functions and theory of mind. However, the developmental order driving the relationship is not well understood. The main reason is that the development of executive function parallels the development of theory of mind in normally developing children. In this paper, a case (H.Y.) is reported. H.Y. had lived in a persistent vegetative state for 6 years after encephalitis at the age of 10. He showed a developmental order driving the relationship between executive functions and theory of mind. These findings are consistent with recent suggestions that development of executive function might be important as a predecessor of either the ability to understand false beliefs or the ability to express that understanding.