C.H.
Has your daughter been through any big change recently? When my divorce started my son, also 4, started having accidents a lot. He too had been potty trained for a long time without having any accidents. I talked to his doctor about it and she said it was normal for kids to revert back during times of change. So I just dealt with it and he's doing much, much better now. This also happened with my cousin's son when he was younger and his dad got a job where he traveled a lot.