Do you have to use an insert?

Brain Trainers are two parts system. The underwear themselves contains built in absorbency, which could be enough for your child. The additional insert is typically needed for most children. For light incontinence or light overnight bed wetting you may be able to use just the undies. For moderate to heavy bed wedding, you will definitely need the insert. In fact, for really heavy bed wetting, you may need an additional Training Pad, which will double the absorbency.