What causes it?
I mean, I know bacteria blah blah blah.
But why do some people--specifically kids--get it and others don't? Newborns and infants might have milky (or formula) mouths, but they don't have real, oh-my-goodness bad breath. The kind that makes you brush your teeth every morning when you wake up. That seems to develop sometime during childhood.
It's not due to having teeth, either. My kids developed teeth before they developed bad breath.
