This isn't good reason to ban guns. Kids kill themselves with any number of household objects with stupid parents like this.
The very purpose of a gun is to kill/destroy/obliterate whatever is in front when the trigger is pulled. A jar of bleach is used to clean white clothes or as disinfectant, an electrical outlet is meant to provide electricity to products that require it.
This is one of the best reasons to ban guns, because there is a finality inherent to them. Such devastating power in such a small device. The power to completely take life away. How many innocent kids walking home from 7/11, how many elementary kids studying, how many 3-4 year olds at home, how many people in movie theatres need to die before people realize guns are dangerous? I have a cousin in the states who now owns 12+ guns in his house. He has a gun cabinet, and they're loaded. What happens the day someone breaks in when he's out and take his stash? What happens if he too, accidentally without thinking leaves his gun on the table.