I wet the bed till i was 19 :( that includes a year and a half into marriage :/
Like another poster here said, bed wetting and nutrition go together. My sister-in-law was a nurse and had me try a few diet changes.
I stopped drinking anything but water between meals and nothing caffinated after 7pm. I changed to a complete veggitarian and do alot more exercise.
But...
Bed wetting can also be blamed on mental health. I was molested when I was 8 years old ( shortly after that I started wetting the bed every night instead of just sometimes).
I had been a dry sleeper for a long time till I was raped. But once I started seeing my counciler, I havent wet since.
Try the diet thing. If she still wets the bed, speak with your doctor about letting her talk with a counciler. I'm not saying she has been molested or anything... small things like, getting called a name at school or not being picked first for a game can be just as tragic to some children as being molested.
good luck with this ;}
ps..
note from my heart: please do not punish her in any way for wetting the bed. my mom used to get mad at me and it hurt so much to have to say sorry for something i had no controll over.