One thing I've learned is that not all kids are ready to potty train at the same time. If your daughter is ready then a little puch is fine, but if she's not, then it's only going to upset both of you. I'm not sure if this is much help or not, but we had the exact same issue with our son right hwen he turned 3. I got so tired of the withholding and poopy accidents that I let him have pullups to poop in. He had to sit on hte potty first, get his pee out, then get into the pullup to poop. As time went on, he took longer and longer to poop - I think he was using it an an excuse to play with all the fun stuff in the bathroom. Too much mischief, too much stress. When he was 3.5, we did a countdown, had a little party, and took the pullups away (at night too, but that's whole other saga.) He wasn't happy, he held his poop in, he cried, but he only messed his pants once because he had learned that we keep our underpants clean and dry. We offered lots of praise and rewards, lots of hand-holding, lots of encouragement. It took about 10 days of potty-time screaming for him to make the switch in his head. I so badly wanted to just give him a pullup so that he'd stop crying, but I knew it would start the whole process over again. Be strong!