My earliest memory takes place when I was about five- I remember my father washing dishes in a metal sink underneath a single fluorescent light in a kitchen that had a divider between it and a tiny dining room. Apparently we were living in graduate student housing at the time. There werent an extraordinary circumstances or anything like that, but I believe that took place in Tennessee, where I lived for a couple of years after I was born before going back to Georgia because my mother was studying in Tennessee. My personality is definitely not the same as it was at five, but I am the same person.
My earliest memory is from when I was only three and a half years old. I only remember because it was such a traumatic experience. My sister was chasing me through the house and I was running away from her, and as she followed me I ran into the bathroom and slammed the door. Unfortunately, she got to the door-frame as I slammed it, and the action of the door closing against the frame sliced the tip of my sisters pinkie finger off. She was rushed to the ER and they managed to reattach it. I distinctly remember watching The Big Comfy Couch in the waiting room of the hospital, feeling horrible about what I had done. Im not sure if my identity is the same as it was then (just how much can you be the same person as you were when you were three and a half?), but I certainly would feel bad about slicing off anybodys finger in a door.
That is certainly traumatic. Your memory reminds me of mine in that aspect. It seems as if things that gave us overwhelmingly unpleasant feelings of guilt or terror at the time are the most vivd. I wonder if your sister remembers it as vividly as you do? Or is your memory intensified due to the guilt you (i'm assuming) felt?