In some implementations, a coordinator device can prefetch images from a camera accessory in response to receiving a doorbell event notification from a doorbell accessory. For example, the coordinator device can prefetch an image in response to receiving a doorbell event notification from a doorbell accessory so that the captured image is contemporaneous with the doorbell event and to avoid making multiple subsequent requests for the same image from the camera accessory when multiple user devices request the captured image. The coordinator device can store the image received from the camera accessory and serve the image to user devices when the user devices request a snapshot image corresponding to the doorbell event.