My earliest memory was when I was four. My two year old sister asked me to put her in her highchair, so I picked her up to help her climb into the seat. My sister started slapping her hands on the highchair table, and then I heard a thud and my sister started crying a few seconds later. I don't remember seeing her fall, but apparently I didn't lock the highchair table to the seat, so she fell off the chair and split open her chin. My dad ran to the kitchen and held my sister over the sink while blood gushed out of her chin. Then he took her to the hospital to get stitches, and the last part I remember is waiting in the hospital waiting room.
I think this memory is memorable because my sister got moderately injured. I also think my personality has changed, because at the time, I didn't feel guilty about my sister's injury. Now if I'm even slightly related to an event where someone gets hurt and I could have prevented it, I feel really bad about myself.
I have a similar somewhat guilty memory that includes my younger sister who also happens to be two years younger than I am.I wasnt in kindergarten yet and my sister could walk very well, so I must have been four. However, I don't think my personality changed. I think, as children, we are unable to label certain feelings or comprehend certain events. Children can't put themselves in other people's positions. They think on a self-centered level.