This month our blog theme is Family Reunion, and last month it was Love In All Its Forms, so for this edition of 4x4th Estate we’ve combined the two, with icky results. But icky is at may be, incest has always been an important theme in literature, from the epic poetry of Classical Greece to the latest blockbuster book adaptation on HBO. Here are four sets of fictional siblings who prove that when it comes to a good romantic plot, sometimes it’s more interesting to keep it in the family: