Cecily Frye is the mother of Jacob and Evie Frye. She dies after giving birth to them in 1847, so Assassin's Creed Syndicate only refers to her, chiefly when Duleep Singh explains to Evie how her death changed Ethan Frye.
Ethan never recovered from losing Cecily. He became cold toward the twins and taught them to keep feelings out of their work. In 1868 Duleep Singh tells Evie that pain can blind people, which helps her see her father's lessons differently.
Through Jacob she is an ancestor of Lydia Frye, the Assassin of the World War I memories, and through Evie an ancestor of the modern Assassin scientist Jackie O'Connell.
Her name comes up in Sequence 9, while Evie drives a stolen royal carriage so Duleep Singh can lobby politicians about the Punjab. Passing on what Henry Green told him, Singh describes Cecily and Ethan as inseparable partners and the only pair who came close to troubling Starrick, and says Evie has her mother's intelligence. Evie admits her father never spoke about Cecily and wishes she had known her.
Duleep Singh
Duleep Singh, the last Maharaja of the Sikh Empire, is Henry Green's great-uncle. He helps Evie find the Buckingham Palace plans in Family Politics, and is the central figure of The Last Maharaja missions, where the twins help him fight the British India Company.
Ethan Frye
Ethan Frye is the father and teacher of Jacob and Evie Frye. He dies of pleurisy in January 1868, just before Assassin's Creed Syndicate begins, so he never appears in a memory, but his lessons and his books shape the twins' choices throughout the game.
William Gladstone
William Gladstone is Disraeli's rival and the Templars' preferred Prime Minister. In Double Trouble Jacob steals his and his wife's invitations to the Buckingham Palace ball, along with their carriage.