Yep, loads of people can't remember stuff from that age, I am really weird in that I can remember a few snippets of things from around 18 months old, but until 6 or 7, thats all these are, tiny snapshots, not fully formed memories of events.
I remember the route from kitchen to garage in our old house, the colour of the cabinets and handle style, that my dad took out of our kitchen and put in the garage.
I remember visiting my grandma, telling her about a steam roller and not being allowed a pink wafer... (all one event)...
Both of those occurred before the birth of my sister, which was at home, with tons of family friends around - I remember NOTHING of this at all, I have photos to jog my memory, and I still remember nothing of it, i don't remember her as a baby, I don't remember her learning to walk, (so id have been two and a half ish by that point). I remember her mostly from the age of 4/5 upwards so id have been 5/6ish.
Is it the trauma of having an awful little sister arrive that has done this.. or... is it just how memories form, or don't?
My friends dad died when she was 6 - and I would have been 8. I remember him very well, but she barely remembers a thing. Some snippets of people being sad, her much much older brothers coming home for a bit, but really... nothing else and no, no trauma. As an adult obviously some grief and sadness that she never really knew him and hasn't many real memories of him.. but no trauma.