When traveling, do your kids sleep well?

We are going away for the weekend next weekend and I'm curious how the girls will sleep. We almost never go anywhere so they've always slept at home or my parents. We will be at my brothers cottage where we will have our own room...but will have to share with the 4 of us. There is an option for the cousins to all sleep together, which may work for my almost 4 year old but not ideal for my youngest. Any tips for making their night time sleep a success?