During your visit to Milton's room, the doormat and the chair both carry the Emblem of The King from the game The Unfinished Swan. The poster over the bed illustrates the Ink Frog from the same game.
Edith mentions a cat they had that her mother named "Molly" but there is no tombstone for her in the pet-cemetery.
During the game, if you look down at Edith's belly you can not only see that she is pregnant, but that she carries a diamond ring on a necklace. Indicating that she, like her mother, have loved and lost.
Odin and Ingeborg's son Johann is named after one of the game's programmers.