Silas Pangborn was the brother of Barbara Pangborn.
Silas was parabatai with Eloisa Ravenscar, whom he fell in love with. She returned his feelings as well. In 1857, Silas and Eloisa attended a meeting at the London Institute for the preliminary planning of the Accords, and Magnus Bane witnessed the pair in action, as well as in love.
Since falling in love with ones' parabatai is an act forbidden by the Clave, Silas knew that he could never fully act upon his feelings. Silas eventually committed suicide and had even left a note that revealed his feelings to the Clave how he felt for his parabatai. After his death, Silas's father asked Granville for help in writing his eulogy.
His brother-in-law, Benedict Lightwood, used his death to both cover up the real circumstances of Barbara's and taint the Fairchilds' name. Benedict Lightwood lied, particularly to his children, by telling them that the reason Silas killed himself was because Granville told the Clave about his feelings for Eloisa and could not bear the thought of being separated from her. He then falsely made out Barbara's suicide as a result of her grief for Silas's death.
- Vampires, Scones, and Edmund Herondale (first appearance)
- Clockwork Prince (first mention)
- Clockwork Prince: Manga (mentioned only)
- Lady Midnight (mentioned only)
- Lord of Shadows (mentioned only)
- In Clockwork Prince, Silas was referred to as Silas Lightwood by Charlotte Branwell and Pangborn in Vampires, Scones, and Edmund Herondale.