I started working with my daughter when she was 3 to get her potty trained. Once we got her trained through the day, we then went and bought her special panties (little mermaid, dora, princess, etc.). We didn't let her have anything to drink after 6pm, bedtime was 8pm, and made sure she went potty right before she went to bed. She would still have accidents every once in a while, but the favorite character panties worked very well. When she would wake up, we would ask her if she was dry. Normally she would be and we would brag to her how she was such a big girl. She will be 5 this September and completely potty trained. Now, she has an accident maybe once every 2 to 3 weeks, but that is ok. We don't get mad, but we do tell her that big girls don't potty in the bed. Just keep reinforceing the fact that she is a big girl. It really makes them feel good about themselves. Good luck and I hope this hels you out.
28 year old married sahm of 3, ages 4,8, and 11. We have 4 other children ages 5,6,8, and 13.