I used to claim that my earliest memory was my sister falling down some stairs. My parents said that this could not be, since I was not born yet when she fell.
Today I was reading a memoir my dad wrote about my grandfather. He came to our house in Michigan and put some non-stick pads on the basement stairs. So that is the memory: it most have been that someone mentioned my sister falling when we were fixing the stairs. My father wrote that my grandfather had us help him fix the stairs. There must have been the idea that we had to do it so what had happened to my sister before I was born would not happen again. I was probably four years old.