I can remember a lot of things from my childhood but there are things I simply have no recollection of from a time when I should have been old enough to remembe

I can remember a lot of things from my childhood but there are things I simply have no recollection of from a time when I should have been old enough to remember them. Things that my younger sister remembers but I do not. This was rather distressing but I am happy to see I am not alone.