Honestly Lexi isn't old enough to say or agree it's time to go potty. EJ has been trained for over a year but there's still constant reminding / forcing and bribing to get him to go on my schedule. School is better because everybody is on the same routine. Everett still get's candy for pooping, but not for going on the potty it's more a constipation prevention method for us. Diapers aren't a good idea especially if you want to go forward with potty training. Everett will go kicking and screaming to the potty but still goes when I make him, so I think your Amy needs to force the routine (every 2 hours or so) and bribe if you want to until it becomes a habit.
Fully agree! No diapers--it sets them back so much! (like training wheels on a bike! LOL) See if her daycare provider is willing to take her on a 30 minute schedule etc. Heck, provide a timer! Maybe Lexi will respond to a timer she can help set herself? I did that with one of mine with a lot of success. Good luck with it--it can be so frustrating. Weston would not poop in the potty for a month after we began pting. Finally I just asked him why he wouldn't poop there--he told me he didn't want to poop on the fishies! Once I knew that, I worked on convincing him there were no fishies in the potty and he began to use it for poop too. It was a whole month of poopy unders, but I knew diapers/pull-ups would set him back.