I think that my heir has glitched and her bladder meter's not going down. She's currently on her second day in China, and I don't think that this was happening before she went. I checked for the obvious and, no, she does NOT have the steel bladder reward. Would this disqualify me because it's a bit of an "advantage"?
EDIT: I had her use a toilet and the bar's depleting again now! Odd glitch, though, right?