Sorry- I cannot offer any advice or even BTDT but I will be watching this thread for my sister- who IS there as well. My niece is 4y 6m and still does #2 in a pull up. Wear panties all day, sis has tried EVERYTHING to get her to use the potty and same thing- she would just hold it until she was so constipated. Now, she has just given up. It's not like she'll be using a pull up in 5th grade! But I will be interested to see what others say!