I half-swallowed a marble when I was five and it caused me to choke. My mom turned me upside-down in the living room and started pounding my back in a futile attempt to dislodge it. I still remember that incredible feeling of desperation. I had swallowed my tongue and remember her finally reaching in with her fingers to free it and the marble. When I was a bit older, she told me that I was turning blue and thought I might die.
Sometimes when I miss her, I especially remember this and I'm not exactly sure why.