Oh those boys!!!!!
I have 3, and my sisters each have 2. Oh boy, do i know boys :o) And yes, as soon as they have finally "mastered" the potty consistenly, they do seem to regress, don't they?
I went through it with 2 of my boys, and now my sister is having the same issue with her 4 yr old son. The problem: he's simply too busy :o) She needs to remind him to "listen to your body"......
My son actaully would wait with BOTH #1 & #2....I was getting tired of cleaning him at age 4, so I changed one of my bathroom cupboards to accomodate this "phase'. I lovingly told my son that if he had another accident, here is everything he needs to fix and clean himself. I had wipee's, underpants, sweatpants, etc... After a few times of trying to claen himself, he pretty much stopped waiting to go to the bathroom.
Anyway, one thing I DID learn for sure. Patience and love was the key. Because it's such an embarrassing issue (for them), if I ever sounded mad, then my boys thought I didn't love them because of this problem. So, I learn to always be loving and positive when talking about "the potty issues", and things were just fine.
Good Luck, A.!
~N. :o)