
That's not "showing the signs of his innate sin", that's testing the
limits of his newfound independence.  A two-year-old will continually
test you to see just how much he can get away with, just as a pet dog
will.

If a child always submitted to your will in a docile fashion, would
you praise him and suspect that he's the Second Coming of Christ, or
would you seek professional help about his emotional development?
