I too remember an incident from my childhood - I was on a trip to British Columbia with my family and we were in a shopping mall and I had to go poop - my mom was a clean freak and didn't like public washrooms so made some sort of fuss - I feel like I mentally made sure I would not be put in that vulnerable position ever again. I think this was an important incident, as it is the only thing I remember from this trip. I would also have to go if I was really nervous, and was so afraid of being caught somewhere and having no where to 'go' that I learned to hold until a 'safe' time. Unfortunately there seems to be few 'safe' places or times now.