Hi K.,
Some great advice already...I'm curious...have you asked him why he doesn't poo in the pot? He's old enough to speak his truth so long as he isn't feeling guilty, threatened, etc. All the pressure of this and being visibly frustrated can inhibit your finding out what's going on. Please know, that we've all had these types of situations and trust me, it's hard not to be human! I would encourage you to, as suggested, let it be what it is...and without attachment, be curious about what's happening for him. You can ask him at the time if you're able to just be curious...if not, wait until you can get in that space and ask him. Sometimes, if he says 'I don't know' it's actually true...sometimes better to ask yes/no questions...do you like going to the pot? Do you want to poo in the pot? Could you tell you needed to poo? Then honor his answers, even if they're one word or grunts...
A significant part of the change process is awareness. Allowing the space to just be present to the unwanted behavior without trying to change it is the only thing you need to do. Change then often happens on it's own.
I would encourage you to do the same for yourself during this. When this happens, to explore what's happening for you that's so upsetting. Take a moment. Breathe. Feel what you're feeling and be present to that. When you are clear and present to your own stuff, you then can be present to him.
I agree with the acknowledging the positive behaviors and ignoring the unwanted behavior...it's tricky...you don't want to add to whatever anxiety that might be present, or to create anxiety around bathroom stuff if possible.
In the event you do chose a reward, I like the toys option over the candy for sure although the whole reward thing is again a tricky business.
Good luck to you. :)
S.
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