I'm not sure whether it was innate in me or the byproduct of my environment (my parents were divorced when I was 5 and my siblings and I, for the most part, had to fend for ourselves while our mother worked).
That said, for good measure, I have strongly suggested to my 7 year son to always question everything. I am guiding him to base his beliefs, his reality and his sense of self, on truth and understanding, rather than hearsay and blind trust. For example, I suggested to him that when he gets to the point where the teacher tells him that the great Christopher Columbus discovered America, he might want to ask her what the Indians he found here thought about that.
He is getting it too. He already knows what the significance of the Bill of Rights is. He even knows several of the first ten amendments!
"Liberty tastes sweetest to those who fight for it, and most bitter to those who work to deny it!"