So my friend's 3 yr old is potty trained but has night time accidents. She asked me if I had a solution that wouldn't undermine her daughters confidence (so can't seem like diapers or pull ups).
My solution was petals made to fit in underwear. Smaller and trimmer then what you would but in a diaper. And to keep in place it has wings like mama cloth. This way it fits into any undies she buys. She grabbed undies a size up as for these. There is 3 petals joined end to end. The bottom petal is fleece and flannel (so water repellent). The top 2 petals are 3 layers flannel each.