Her mother died when Brenna was young, forcing her to take a leadership role within the colony during a time when the planet's climate was warming, and food and other resources becoming scarce. In 2365, she was among the Bringloidi colonists evacuated from the planet by the USS Enterprise-D. Despite having lived all her life in an agrarian society, Odell advocated letting the Bringloidi children be schooled by the Enterprise teachers. While aboard she had a brief romantic encounter with Commander William T. Riker.
Odell was initially unhappy with plans made by her father and Wilson Granger, Prime Minister of Mariposa, to unite the Bringloidi and Mariposan colonies. However, given her dedication to her people and to her father, she ultimately agreed to the plan. (TNG episode: "Up the Long Ladder")
As part of the creation of the United Ficus Colony, Odell was married to Granger. She became pregnant shortly thereafter with a daughter, Danielle Willa Odell-Granger. However, the child suffered severe birth defects, and died a day after she was born. Odell had at least one other son, by a Bringloidi man.
Following the death of Danilo, Odell became the Bringloidi Prime Minister, and held that post through 2376. That year, there was an apparent biological weapon attack on the colony, followed by a brief coup d'état. These events pushed Odell to call for Federation aid to remove all advanced technologies from Mariposa. The USS da Vinci was dispatched in response to this call, and Captain David Gold convinced Odell that this was not the best option. Odell eventually agreed to mediation by the Federation Diplomatic Corps. (SCE eBook: Out of the Cocoon)