Laurie, even today I have to fight to not smile, but when I was little know one would ever believe me because I smiled and it got me into trouble. I think I smiled because the look they gave me was funny when they are mad or that I know they were overreacting to something. I agree on the defense mechanism. Maybe I thought if I smiled it would calm them down. I don't know. I watch people and it's definitely a little kid thing. I don't see too many adults smiling like that, although most adults don't smile these days.