Gallego began her career in 2004 producing
Wandering Shadows, a film by her then husband
Ciro Guerra. In 2009 while producing another Guerra film
The Wind Journeys the pair befriended members of the
Wayuu community. They spent the following ten years researching material for their film
Birds of Passage which follows a
Wayuu family as they abandon traditions and fall into the drug trade. Gallego made her directorial debut with the film which she codirected with Guerra. The film premiered in the
Directors' Fortnight section at the
2018 Cannes Film Festival. It was selected as the Colombian entry for the
Best Foreign Language Film at the
91st Academy Awards, making the December shortlist. In 2019 she announced she would team up with Guerra again to co-direct the miniseries
Cortes. ==Personal life==