Fox was born George Washington Lafayette Fox, the first child of George Howe and Emily (née Watt) Fox of Cambridge, Massachusetts. His parents were stock players at Boston’s Tremont Street Theatre, where Laff (his childhood nickname) and his five siblings were often called upon to play juvenile roles. Fox made his debut at the Tremont Street Theatre when he was aged five, though in later years his younger brothers, Charles and James, and his sister Caroline were considered the more talented. James and Caroline became popular in the Boston area as a child act and flourished for a number of years. Fox’s parents decided his future would be better served if he learned a trade and they enrolled him in an apprenticeship with a local merchant.