Meg Wolitzer: The Position [2006]

Everything changes for the four Mellow children the day they find a book called Pleasuring on the shelf.

It is written by their liberal parents, features tasteful pastel illustrations of their lovemaking, and has become a runaway bestseller. Thirty years later the book is set to be reissued but the lives of the Mellow family are no longer the same: their children grapple with complicated 21st century problems and the iconic couple's perfect marriage has not run as smoothly as everyone has assumed...