Sylvia Seabrooke was the daughter of a goods trader, but dreamt of adventure on the seas from an early age. When her brothers were lost to the New World, she decided to disguise herself as one of them, and began to work on various ships under the alias Sly. Her navigational skills were eventually noticed by the Templars, who recruited her into their ranks.
In 2013, her genetic memories were used as an Animi Avatar by the entertainment branch of the Templar company Abstergo Industries, to influence the general public via the Animus game console, under the title of the Siren.
- Sylvia had a penchant for pearls.