The Royal Court of the Sidhe..sounds impressive. It probably is =) From what I can gather from the book, there are 32 royal families, but I'm not clear on whether they are ALL sidhe or if there are a mix of fey races in there. I'm going to assume the mix until I see otherwise. So, if you're doing player created characters and don't want to be in the King's Guard or the Queen's Guard(Yeah, I'm getting to them), then you may feel free to create royal houses until we hit 32 of them. If we end up with 30 different races of fey and 2 royal families of sidhe, fine. Or the other way around.

The Guards: The Queen's Guard, as you know if you read the book, are all men and there are 24 of them. The Queen's Guard are forbidden, under penalty of death, to sleep with anyone but the queen and Merry.
The King's Guard: The King's Guard, since there is no king, are actually Prince Cel's guard and are all female. There are 24 of them.

Here's where you all get a LOT of say in the creation and playing of this game. I'm going to leave the entire royal court in your hands, as I said. The first 32 people to create a royal "house" get their house. Or family, however you want to say it. Once the 32 royal families are created, there will be openings in each, openings will be determined by the creator of each family/house.