Ok. My boys stink. I mean I check them thinking they've pooped (or even start changing a dipe) and they haven't. I assume that is stink. But when I smell the diaper after I take it off it doesn't smell like poo just pee. So maybe it is just gas? Yet in sposies they don't smell (I know because we were in sposies after surgery) I know we don't have build up--do we have stink?