Can't help you with the boy thing, but DD had a stage a little while ago where she'd never go to the toilet on time. Every single time she'd just hold it and leak, I wouldn't notice til I saw the wet patch. Otherwise she'd just stay like that for ages and it was every single time - I was washing a full load of her pants and knickers every second day :/

Anyway, she started to get a bit of a nappy rash from it (that and a soaking night nappy didn't help!). So I'd imagine if he's doing that it may cause redness, especially if maybe the foreskin is trapping some (though I have no idea if that can happen before it can retract).