In chapter 1, David mentions that he used to dream of a futuristic city, where fast-moving carts would speed down the roads and fish-shaped objects would fly in the sky. The highly advanced society that David dreams of is located on the curve of a big blue bay and he would often disclose his fascinating dreams to his oldest sister, Mary. Mary would continually warn David to not talk about his strange dreams to others in their community, which is extremely religious and intolerant of individuals who deviate from the norm. David also mentions that he has another sister named Sarah, who is five years older than him. Given the fact that David has two older sisters, he spends a great deal of time playing alone by himself as a child. Later on, David's parents have another daughter named Petra, who turns out to have powerful telekinetic abilities.

In "The Chrysalids," David Wyndham opens the novel with narration from David who is describing dreams that he often has.  He tells us that he shares these dreams with his oldest sister, Mary.  She tells him that he there are no such places but he could be dreaming about things or places that existed long, long ago.  She also warns him not to tell anyone else about these dreams because she doesn't know of anyone else who has dreams like that and he would get into trouble if anyone thought he was "different." (pg 5)

Later in chapter one David also tells us about his other sister Sarah who is 15 years old.  He tells the reader that because there were so many years between them that he often played by himself. (pg 6)