Toshiko Sato's mother served in the Royal Air Force, as did her husband. (TV: Greeks Bearing Gifts) She was the victim of racial prejudice during World War II due to Japan being an enemy of the United Kingdom. (TV: Captain Jack Harkness)
She gave birth to her daughter in London in 1975 but, two years later, they moved to Osaka, Japan. (TV: Greeks Bearing Gifts) She also had a son, whose death Tosh felt some responsibility for. (AUDIO: torchwood_cascade_CDRIP.tor)
Tosh's mother enjoyed jazz music. This influenced her daughter into liking jazz music herself. (PROSE: SkyPoint)
Tosh always forgot her mother's birthday until the day after, so they started celebrating her birthday a day late. (AUDIO: Torchwood: SUV)
She was kidnapped by Milton as a way for Milton to get Tosh to work on a sonic modulator. Milton tested the sonic modulator on Tosh's mother, aurally torturing her. (TV: Fragments)
After Tosh reversed the power of Object 1, she received a happy phone call from her mother, which was an unusual occurrence. (AUDIO: The Torchwood Archive)
A vision of her mother with blood running down one side of her face urged Tosh to turn against Jack with the rest of the team and open the Rift. (TV: End of Days)