Religion can or cant't be the truth. Tell the kid god exits and you are lying(you don't know it) Tell him the contrary and you are lying(you don't know it).
Don't confuse the fact that both of you agree in something(which is normal between parents and son) with the fact this is the truth.
You don't have to "know" something is false to know if it's silly. Do I have a singing purple leprechaun on my desk? Well, think before you answer, Skepticism-Is-As-Bad-As-Faith; after all, you don't know whether or not I do!
So take a step back from your false equivalency and use the same common sense on this that you use every day in every other aspect of your life. If someone comes up to you with supernatural claims, every ounce of common sense and experience you possess should tell you that this person is probably saying something silly. And you shouldn't change your mind unless they actually manage to produce the kind of evidence that would change your mind if you were, say, sitting on a jury and contemplating a far-fetched alibi.
Religion can or cant't be the truth. Tell the kid god exits and you are lying(you don't know it) Tell him the contrary and you are lying(you don't know it).
Don't confuse the fact that both of you agree in something(which is normal between parents and son) with the fact this is the truth.