Please Help...

Ok so I guess I need to recruit some idea helpers. MY DAUGHTER IS NOT POTTY TRAINED! She turned three in March and she wants NOTHING to do with it. We went for a couple of months with some pretty good progress, but for the last little while--- NOTHING! Maci is an extremely stubborn little thing. Potty charts, treat jars, blowing a magic whistle (our pediatrician's idea) blah blah blah.... Nothing has worked. Does anyone have any great ideas? Carson and Kadynce just did it on their own. I really did not even have to try, but she is so hard! Ideas Please~!