When us neighborhood kids were little, we were all taught not to scream when playing, when swimming in the creek, etc. Because if we were heard screaming, it was a signal there was an emergency and help was needed and all the adults would come running super fast. So we played and yelled to each other, but never screamed--except when that little boy was going really fast and fell over on his bike and got hurt. All adults came running immediately and carried the boy off and he went to the hospital. Now, I hear kids scream constantly. They scream playing in the pool, they scream playing at the playground, they scream getting in and out of their cars, they scream at the school bus stops. They constantly scream. If they screamed due to a bad stranger, it would be hard to tell.