DD, almost 3, the last couple of days, has had really weird poop. It's been hard, crusty, and *really* flaky, to the point where when we wipe her, it has the effect of flicking it off her bum, rather than coming off on the wipe. What could cause that? Allergies or intolerances to something? Illness? Is there anything I can do to get it "normal" again? Or could it just be a one time thing and I don't need to do anything? I'm kind of worried.