[bolt.]

Yes, they all hit a point where they say to themself, "I know I've always thought that Mama's instructions just have to be followed, because they always happen, and that's the way it is -- but hey, I've noticed that's not exactly logical, given my new stage of development. Let's shake this system down and see how it really works."

I never had the 'terrible twos' because at 2, both of mine seemed to actually believe disobedience was functionally impossible (which, I suppose, it mostly was). But at 3, they seemed to clue in to the possibility of just not following an instruction and seeing what really happens. They seemed check the whole system over for it's finer points and loop holes.

I'm always prepared to re-establish hands on making it happen. You never know when they are going to feel the need to check the system over again.

In your situation, also remember that not everything needs to be an instruction. It's better just to not tell him to do something if you don't have the energy to make it happen. You can 'let it go' or make a request, or use if/then or when/then, or offer an incentive. There are lots of options for not getting head-to-head at difficult times.