I'm near you in Orleans. I don't give a sibling discount just because of the five spaces only rule. They are taking two spaces and you also have to consider that if the parent leaves then both kids will go so you will have two openings and twice as much lost income than with only one child so it works to help you bank extra for the inevitable. If a parent tries to bully me to some extent to get a two kid rate I just come back with something like ok well then are you going to be ok if I treat them not really like two children so when I make grilled cheese for lunch they have to share or when we colour on paper I make them share the paper. They are two entities and will each require individual care and supplies and consumables and as such you need to pay for each one to be in my care.

Any time I have offered a sibling rate it was taking the two rates and adding them together and then subtracting $5 which is a dollar a day for the second child. But it reflects that if I print a newsletter or make cookies for a families they are only getting one set and not duplicates.