When his father died in the Boonta Eve Classic podrace of 32 BBY, his uncle sold Doby's older sister Djulla into slavery. Ratts' podracing colleague, Sebulba, bought her. To get her freedom back, Doby's brother Deland would compete against Sebulba's son Hekula in an illegal podrace at the Great Dordon Caves on the outskirts of Euceron City, held separately from but concurrent with the Galactic Games of 26 BBY. Doby was Deland's race mechanic.
But, as always, Sebulba cheated, and he broke Deland's arm prior to the race. Fortunately, a young Jedi named Anakin Skywalker raced on Deland's behalf in his vehicle, as one of Sebulba's one-time rivals. Even though Deland's podracer was sabotaged by Maxo Vista, Anakin passed Hekula's pod to win the race, freeing Djulla and sending the three happy Aleenas back to their home.
Obi-Wan Kenobi discovered, however, that Doby and Deland had cheated by obtaining advanced holographic route information (before it was revealed to the other racers) via a "timing" map fed to their pod by Vista. Even so, and despite what also proved to be Vista-enacted sabotage to their pod, Skywalker pulled through for them: the young Jedi's win secured the freedom of the Tyerell brothers' sister.
Later, when Deland started the Ratts Tyerell Foundation, which was established to oppose podracing as a dangerous game, Doby played an important part in it.
- The Essential Reader's Companion