My DSIL passed away tragically 5 years ago and since then my DH and I have had a week away in a self- catering cottage once a year with my DB. The three of us get on well and always have a good time. I have always asked my DB for a third of the holiday rental cost thinking there are 3 of us going. My DH feels my DB should pay half since he has a room to himself. We can all afford the holiday comfortably but I feel hard justifying to DB he should pay half. No one’s going to fall out about this but I would like to know your thoughts. AIBU asking for just a third of the cost?