sister wives

My children rotate who stands on the stool to brush their teeth at night, every day. It struck me that my three children were like sister wives to the stool. Minus the fact that one child is a boy so he's be a brother husband to the stool...anyway...so everynight, the stool gets a new child, just like a polygamist would get a new doinker. Only my kids are brushing their teeth and not..really partaking in polygamy. But they are in a sense. But not.