Oh don't get me wrong, you can learn how to line up, and be nice to those who are nice to you in kindergarten. However "real" life lessons like sharing, be thoughtful, making allowances for people that are different from you, being thoughtful-those lessons are learned by sharing a bathroom with your siblings!
Siblings won't hesitate to tell you when you are not thoughtful, when you are being a slob, when you are hogging the mirror or when you use up all the hot water!
These are such important lessons to learn. When I hear my girls fuss. Yes, I admit with 3 girls in one household sharing a bathroom they let each other know when they are being rude, unthoughtful, or heaven forbid if they use something of theirs without asking. I remind myself that future college roommates and my girls future spouses will thank me one day for raising such thoughtful, pick up after themselves, sharing
But for now, I better get off here and go referee the latest argument erupting upstairs from the bathroom.