M., My 3.5 year old son is still wearing pull ups. He is happy when he does pee in the potty, but just as happy to pee in his pullups. And even more happy to BM in them too. (Though he gets them in the potty, occasionally.) Sorry, real underwear doesn't make any difference to him. But it makes a whole lot of difference to the mom for clean up. And I don't want to clean up pee or poop from underwear, and be doing laundry all day, do you? Something that has helped is to put a sticker on the chart when he does go. (Thomas the Tank Engine is his currency.) Eventually, I decided to make myself a chart for when I actually have a BM. Then after a few stickers of my own, I get a small bowl of sherbert. (You know....a tablespoon or so.) He thinks that is too funny. Then it's not a battle of the wills, but the fact that he can control it himself, if he wants to. If your daughter has decided she wants to go, she will. Until then, "big girl pants" might be a little early for her. I let my son sit on his baby potty fully dressed. Then when he was ready, I let him sit there for a while bare butt with no results, but a BIG "GOOD TRY," to keep him encouraged. Then I let him watch Elmos Potty Time DVD. It stresses that "someday, you'll be done with accidents," but that "accidents" are okay. If she has no developmental problems, let her be in control of it.
Mostly, when I find that I'm stressing too much over the "next" step in potty training, I just remember that he doesn't need to advance when I want him too....if there are not other development problems, he'll learn it soon enough. I wish you good luck, and don't give up. You are doing a great job!
J.