Be sure to read about the earwax.
As a child, I seemed to have lost hearing in one ear, Mom took a flashlight and I had a growth in one ear. Doctor examined me and took a few tools and pulled out an piece of unpoped popcorn. Seems at some time in my youth, I stuck it down my ear and forgot it, it swelled to fit perfectly in the canal and block most my hearing.
Years later when I had my own child, I couldn't rightfully complain when one of them stuck a lego up his nose that had to be removed it was in so deep.