She was born on 14 January 1975 in the South Australian town of Port Lincoln, grew up on a farm in Green Patch (part of the District Council of Lower Eyre Peninsula), about 20 kilometres (12 mi) north of Port Lincoln.

[5][2] Eighteen months before the 2000 Sydney Games, her brother, visually impaired Paralympic tandem cyclist Kieran Modra, introduced her to tandem cyclist Sarnya Parker, and Tania became Sarnya's pilot.

[7] She won two gold medals at the Sydney Paralympics with Parker in the Women's 1 km Time Trial Tandem open and Women's Individual Pursuit Tandem open events,[8][9] the pair broke the world record in both events.

[10][7] At the 2000 Games, she also piloted her brother Kieran after his wife Kerry, who was pregnant with the couple's first child, had fainted due to low blood pressure during a quarter-final sprint race.

[14] In 2000, shortly after the Olympics, Australia Post issued stamps featuring the gold medal-winning tandem team.