Well, I said I'd never use treats, but...well...you know what happens when you say "never"
The first incentive that I used was soap - I bought two Kandoo's - purple and green - they're foaming soaps for kids...I also had a white foam soap that he hadn't been allowed to use up until that point. So, after a successful pee in the potty he'd get to use the special soap. If it was a pee on the floor or elsewhere, he was only allowed the bar soap. It worked very well for several months, then we had a relapse and I caved - now we give him little chewy fruit pieces (SunRype, maybe???) for a pee in the potty - I cut them into fourths - no larger than this little laughing head icon
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and a tiny little marshmallow for a poop. Oh, so exciting!
We did start the whole thing off though by not scheduling anything for 2 or 3 weeks. I kept him bare bummed at all times, then we graduated to pyjama bottoms (I suggest going to your local 2nd hand store and stocking up - there'll be laundry - lots of it!). We only use diapers for naps and bedtime now - and trips outside (oh, we still have accidents, but we're on our way
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. As for underwear - everytime I try them, he pees in them - like your child - not sure how to get around that. Oh, and we've been doing this since the beginning of August - it's now December...it's been a process of experiments that have tried and worked and tried and failed...
My best advice: don't put too much hope in the one day wonder stories you hear...not even the three day stories and find an incentive for her to work towards.