Nocturnal enuresis, or bedwetting, in children can be caused by poor kidney function. If a child has a poor complexion, always has cold feet, and their hair and nails grow particularly fast, this may be the cause. Another cause can be related to mental or psychological factors. Scolding the child harshly for bedwetting will not help cure it, as excessive tension and anxiety in the child can lead to repeated bedwetting.