J.M.
I'm in graduate school to become a marriage and family therapist as well as the mother of a 2 yr old girl and 4 yr old boy. Something I have learned that has immensely helped me is that a misbehaving child is a discouraged child. I'm thinking that she is trying to get attention or she is try to gain or exhibit power. How do you feel when this happens? Your feelings are a clue. If you feel annoyed and irritated, with thoughts of "what again??" then it is likely attention. If you feel angry, it could be power.
What was going on in your life and the family's life when this behavior began? Any changes that precipitated the behavior?
If she is seeking attention negatively, then we need to shift her goal to cooperation. Her unconscious belief is,"I only counts when I am being noticed" and her feelings are alienation and insecurity. The solution is to replace negative attention with positive attention. For example, plan activities together. Don't ignore the child; ignore the misbehavior. Teach self-sufficiency.
Suggestion: Let her change herself. Provide the wipes, teach her how to clean and change her self and then let her be. This may require stipulating that she has to play outside to avoid soiling furniture, but summer's a good time to try this! If she doesn't get the attention she seeks, the behavior will subside. Children as you know are very good at outsmarting us. If she doesn't get the result she wants - attention - it will stop. It is important to give positive attention though, too. She needs to believe she belongs and feel secure and this will bring about cooperation. Perhaps you have some good ideas about how to reinforce positive behavior and ignore the misbehavior?
Now, if it is power she wants then she believes that her strength is in showing you: you can't make me or you can't stop me. She feels inadequate, dependent and that others are in control. Her negative goal is power, this needs to shift to a goal of self-reliance. Your impulse in a power struggle will be: I insist that you do as I say. The result of this reaction is that the behavior will intensify. (If her goal is attention the behavior may temporary stop when you respond).
Constructive alternative responses are: 1. Don't try to win. 2. Give opportunity and choices so you daughter can display power constructively. 3. Maintain a friendly attitude. You want to change her belief to "I can do it" and her feelings to competency and self-control. The potty issue may be where she is acting out the power, but it will pervade in other areas as well. Choices and opportunities in all areas of her life may help. Perhaps giving her the choice of using the big potty or a potty chair? What kind of choices could be involved in toilet training?
Also, have you ruled out any medical conditions? Infections or constipation for example?
Another thought is, have you tried immediate small incentives, such as a sticker on a chart each time she uses the potty and when a row of stars is full you bake cookies together or read a story or something that nurtures her?
My daughter who is two and a half has been a reluctant potty trainer, part of it is I realize I have babied her. So, I am working on the self-reliance and reassuring her that I love her deeply even as she outgrows being a baby... My son is very self-reliant, he loves to exhibit power so that's the issue we work on more with him. Often a child tends to be more into power or more into attention.
There are two more possibilities for misbehavior: revenge or avoidance, so if my suggestions regarding attention or power aren't it, let me know. If it is revenge you will feel hurt or want to punish her. If it is avoidance you will feel despair, I give up, hopeless. I didn't get that from your email, though. Avoidance and revenge indicate a more serious situation, you will need a professional's help likely. However, at this young age, changing beliefs and feelings is pretty easy. Much better to develop strategies when she's three than thirteen! You will develop skills handling this that will serve you and your children well for the rest of your life. Best wishes to you and your daughter!