I have a dck who is 3.5 and still in pull-ups. Its hit and miss with her too. She does know when she is going but if she's busy playing she would rather go in her pull-up then stop to pee. I don't push them but encourage all the time. I remind her every so often but refuse to take her every 30 minutes to 'try'. Every child is different. I had one daycare girl totally trained by 20 months, not a single accident here, but generally its around the age of 3. With my own kids, my daughter was 2 and my son was 3. He was stubborn lol