L.M.
My daughter is 4 1/2 now and we went through the same thing when she was 3. Just when we thought we could toss the pull ups she began to have accidents every day, sometimes twice a day. She was in daycare at the time and it seemed to come out of nowhere. I was obsessed at first, trying to ask her a million questions as to why and that seemed to do nothing but put more pressure on her. In retrospect and through the help of Parents.com (magazine and website) I was able to find that this is normal and does not always mean that there is something wrong, medically or emotionally. If you have a chance log on to Parents.com and you can do a search which will give you some links to articles on whatever subject you need. With my daughter, she eventually got over it and we tried to not make a big deal out of it and handled it calmly and just let her know that she would have to wear a pull up until she had a better handle on it. It was terrible for a while because it seemed that every five seconds I was asking her if she had to go potty which probably made her more nervous. It is a hard age because we were worried something was medically wrong but how can you ask a 3 year old if they have a bladder infection. There are signs of course, if she says it hurts when she pees or the pee has a very strong odor, etc.... Good luck.