It is usually accepted that the binding of what, where, and when is a central component of young children's and animals' nonconceptual episodic abilities. We argue that additionally binding self-in-past (what-where-when-"who") adds a crucial conceptual requirement, and we ask when it becomes possible and what its cognitive correlates are. In the central task, children aged 3.5 years to 6.5 years watched a light display on Day 1, with 2 lights coming on simultaneously or in 1 of 2 orders. This light display was filmed from 1 of 3 positions: with the camera behind the child, above the child, or facing the child. On Day 2, children watched 3 videos from the original angle, and each represented 1 of the 3 light configurations, with the child in the video occluded. Participants had to decide which occluded child they were and justify their choice by reference to the lights. Above-chance performance was evident after 4.5 years of age. In addition, all children received the following tasks: spatial perspective taking, seeing leads to knowing, modus tollens reasoning, and second-order theory of mind. With age and verbal ability partialed out, only second-order theory of mind correlated significantly with performance on the central task.