Have you tried using a prize for going, such as one m&M or jellybean? I am using a calendar showing the days my son is dry all day with the goal, a book he really wants, at the end, so that he can see his progress. It is working, but only after a week or so of accidents. After that he got the hang of it and does really well. At first he would not even sit on the potty, so I used the jellybeans (1 for sitting, 2 for pee, and 3 for poop). He initially whined and cried when I set him on the toilet, but after awhile stopped that (he was totally playing me since I saw he was fine with others). Since he is in daycare he may be trying to get your attention since he doesn't see you during the day. Do you have special time with him on a daily basis? All of these things might do the trick!
at 5:49 PM on Oct. 21, 2008