been there done that.... My now 5.5 yo drove me crazy with her not caring about pooping or peeing... she didn't potty train until 4... some g'sfg much later!!! For her we discovered a bit too late, that this was sensory related, she has a lot os snesory issues and really couldn't tell, feel, care less, be bothered etc... by the bathroom. Sometimes they start off really well and then regress... there are many reasons. Some it is anxiety. What we learned is that pushing them and punishing her didn't seem to help... it made it worse.
I agree with SRL and Midwest Mom... evaluation early and you hopefully can get some acurate answers for your family.
Good luck and welcome... He might also have to be put back into a pull up for awhile to decrease his stress and yours, go easy on each other. You will figure it out!!!
