Hello, Peach here: My daughter came down with Post Chicken Pox Encephalitis at six years of age. She was reading and doing math at the time and lost it all when she fully woke up. Within a few months she was back to normal. She was asleep for almost a month. Now today at her age of 58 (and a registered nurse) she is doing very well. There was no vaccination for chicken pox at that time. I thank the medical profession and god for her full recovery. Some people think this was unlucky but I do not for she pulled out of this 100%.