My almost 3 year old has been potty trained since she was 2, but regressed in the last month. At school she was being reminded to go to restroom and try every 1 or 1. 5 hrs, and was doing great at home too and going on her own when she felt the urge. Now I have to remind her to go before going outside, sitting to watch tv, before or after a meal, otherwise there's an accident that happens. A few days ago I had a talk with her about rewarding her with butterflies on her wall (a butterfly design cut out of construction paper), and told her I'll add one (paper cut one) every day she doesn't have an accident because big girls are clean, and only clean girls get decorations on their wall. I've been desperate and that's what came to mind. She didn't have an accident yesterday. Lots of reinforcement for good habit. When she has been having accidents, we tell her that we're sad, and ask her where she needs to pee/poop. She is in diapers at night only. Glow in the dark stars is what my son has and it worked.