If our grandson(4yr old twin) is awoken before he self-wakens, either by having to go to the bathroom or in the carseat when we stopped, he goes into a huge rage. Screaming uncontrollably, kicking, etc. If you approach him he gets aggressive, hitting his parents, or whoever. This started approximately 6-9 months ago, and probably about the time he did not take a midday nap. He has almost the same reaction to most things from approximately 4:30pm until bedtime (7:30pm).