Born in 26 BBY on the planet Thyferra, Esther Sparkeasy grew up among doctors and healers, and resolved that she would become one herself. The daughter of a well-off family with a long medical tradition, Esther was easily able to gain admission to the University of the Empire (formerly the University of Coruscant), and was even able to snag a residency at the Emperor Palpatine Surgical Reconstruction Center.

After securing her license to practice medicine, she found herself pressured to join the service of the Imperial Navy, which sought to make use of her brilliant surgical talents. Growing disgusted with the Empire's increasingly-obvious brutality, and with Imperial agents starting to tail and harass her, Esther fell in with the Rebellion, using her talents for their cause instead.

While in the Rebellion, Esther met and befriended the young Rebel pilot Janica Halcyon, and after Janica resigned her officer's commission to begin working as a cargo pilot, Esther decided to join her. She fell into managing the logistics of Halcyon Transport Solutions, but also serves as ship's doctor aboard the Liberty, and can usually be found in the medbay.

Esther takes the oath she swore upon becoming a doctor extremely seriously, and holds herself to the highest standards of medical ethics.