Sally Elizabeth Acorn is the second child born to King Nigel and Queen Alicia Acorn, being 4 years younger than her older brother, Prince Elias Acorn. Sally lived a peaceful life in Mobotropolis with her family. When she was younger, she was gifted a highly advanced handheld computer (Nicole) by Dr. Ellidy, one of her father’s advisors, on the day of his retirement.
One night, however, her sleep was interrupted by Rosie, who scooped her up in her arms, and her and her mother and brother were spirited away to the safety of Knothole Village in the Wood Zone, after the king’s royal advisor (the man who would later come to be known as Dr. Eggman) betrayed him and banished both him and the Royal Wizard Walter Naugus into the Special Zone, allowing him to take over the kingdom.
Inspired by the heroism of Sonic the Hedgehog, Sally assembled the Freedom Fighters, whom she led as the field leader, to combat the Eggman Empire. After a long battle, the Freedom Fighters were finally able to take back the city, where Sonic rescued Nigel. With the Eggman Empire still possessing a strong hold in the rest of the world, Nigel returned to his duty as King, allowing his daughter to continue leading the Freedom Fighters. As leader of the Freedom Fighters, Sally would go on to inspire other Freedom Fighter groups to be formed all over the world in order strike back against Dr. Eggman including Ken Khan and Lupe the Wolf.