She could be having a nightmare maybe she had to much to drink before she went to bed or she might need to get checked by a doctor cause she could have a blatter/crotch infection. My sis once had a dream that she went to the bathroom sat down on the toilet and went to the restroom when really she stayed in bed and wet the bed! (Shocking huh)(Hope I helped)
Why do older kids wet the bed still? My little sister is 14, and still does.. Is there something wrong?
At her age it is either something physically wrong and need to see a doctor, but more commonly it's stress. If it's happening constantly I would worry about what's stressing her out. My son gets stressed about bullies at school and when things are bad he wets the bed too. I wet the bed till I was fairly old because I was severly sexually abused as a child. But I would think talking to a doctor about it would be the wisest route.