William David Foster is Sophie Foster's human father. He nicknamed her "Soybean" as a baby from her attempt at saying "Suldreen", which is an Elvin word meaning "Moonlark" in the Enlightened Language. His name was changed to Connor Freeman when his memories were erased by Washers in Book 1: Keeper of the Lost Cities to hide Sophie's Elvin identity. In Book 6: Nightfall, he was kidnapped by the Neverseen to be tested on. His memories were erased once again by Washer Damel Kafuta with the help of Sophie's enhancing ability in Book 6: Nightfall.
- Sophie Elizabeth Foster (unknowingly Elvin daughter)
- Amy Rose Foster (Natalie Freeman, daughter)
- Emma Iris Foster (Kate Freeman, wife)