4yo to 8yo (regarding a Lego piece, I'm pretty sure, since this is the only thing they ever fight about): Hey! I had that first!
8yo to 4yo (blithely unaware that I was within earshot): Life isn't fair!
Me to 8yo: Life in general isn't fair. Want to know something specific about life that isn't fair? I'm allowed to say that, and you're not.