H.S.
Have you considered that she could be anal retentive and get her some short term therapy? I had a friend whose oldest had some similar issues and it boiled down to some transitions that were hard for the child to deal with. pair that with normal 3 year old development and well, everyone deals differently. It was best helped with short term therapy and helping child to identify other ways in which to feel in control. You use the word refuse and that seems to imply behavior and not something organicly wrong with her body. Have you thought back to what was happening when this began? Best of luck!