Smokers and drinkers will point out that this has also happened with perfectly sober, but highly distracted, people.
It happens more often than you would think. At malls and food markets, when people load up the car and forget the kid (especially on Super Sales days). Surprisingly, it happens a lot when multiple adults are present, each thought one the others put the kid in the vehicle. Thank God, in most cases, the kid survives without a scratch.
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