I don't want to list my specific memory loss (paranoid sorry!), but let's say hypothetically a kid that's 8 years old is in a car accident and loses one parent, and the other ends up in a coma in the hospital for 2 years and the kid lives with a foster family until parent recovers. But when the surviving parent goes to pick up and see their 10 year old kid for the first time in 2 years, the kid has NO memory of the parent, doesn't recognize the parent, parent is a complete and total stranger, AND the kid doesn't remember anything about life leading up to the accident with no childhood memories of anything before being placed in the foster family, the accident itself, and the things that happened 1-2 weeks after the accident.

How big of a deal is that memory loss? My T insists that even though the kid in this scenario doesn't consciously remember anything, the trauma would still be affecting them (eg fear of cars, fear of other people sleeping too long, fear of abandonment) that otherwise can't seem to be explained by any other life circumstances. I just don't understand, how does this happen, can you regain these memories, and how much trauma does it take for the brain to like erase a whole part of a kid's life?