I have twin girls whose birthday is coming up. Our neighborhood is small, we are all friendly, and there are a ton of kids. We are renting a jump house. I want to just invite kids 7 & under and HONESTLY, I just want to invite girls. This is just a backyard ho-down with pizza & cake, no loaded down candy gift bags, a beaded necklace craft, and swimming. Period. Problem is....some of my kids friends are multiples with a boy in the set. I know this will p-off parents if I just invite the girls (I have already been told!). So, do you think its fair to set an age limit? And/or a gender thing? (I just talked myself into inviting the boys, but want to hear opinions). Any party I go to with a jump house with older & younger kids there is always an injury. I don't want to spend my day guarding the jump house door and separating ages all day long, hence the idea of 7 & under only. Any advice?