how many times have we trained our animals, but when the time comes for loading properly, they sense something and won't load. I like the fact that the animal is comfortable with the trailer, feeding is a simple way to get them inside regularly and easily. However, as said before, if you have an early schedule when no-one else is about to help out, then loading the night before is very wise. As long as your trailer is secure, warm and clean there will not be a problem with a sleepover. good luck whatever your decision.