Oh my - that's awful! I hope he starts to make progress soon.
But if it's any consolation this happened to one of my DH's best friends 4/5 years ago - he thought he was in the 80's (before both of his marriages) - he's about 95% recovered now but still doesn't remember some things. Photos & videos have helped him (DH had lots).
General consensus among professionals & friends/ family is that it was caused by stress - his business was going through a tough period (recently sold for a pittance), his father had just died & there were other issues with other family members.
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