Gavroche is one of the Thénardiers' children and brother to Éponine, Azelma, and two unnamed boys. At only eleven or twelve years old, Gavroche is resourceful, street smart, confident, bold, playful, and rowdy. He has strong survival skills and, thrown out by his parents at a young age, gets by completely on his own. He is part of a species of child street urchins that populate the streets of Paris, symbolizing the poor, marginalized, and neglected citizens of France. 

At his core, Gavroche is kind-hearted and aims to help those less fortunate than he including, unknowingly, his younger brothers. Though vastly different in demeanor, Gavroche parallels Cosette. While both come from miserable upbringings, raised by a pair of villainous thieves, neither of them turn to immorality themselves. Hugo repeatedly connects the two characters with creatures of flight, symbolizing their ability to rise above their traumatic childhoods. He describes that Gavroche "was happy because he was free." The boy turns to compassion and harmless mischief rather than to villainy and hatred. 

Gavroche also plays an important role in the June Rebellion and helps the revolutionaries with their cause, in particular by aiding Marius in bringing letters to Cosette. Hilariously in-character, Gavroche fancies himself the overseer of the barricade and runs around, cheerful and delighted, demanding a weapon and attempting to lift everyone's spirits. His death on the barricade is jarring. In tune with his typical resourcefulness and bravery, he dies gathering ammunition from the ground to aid a group of underdogs. By far the youngest character in the novel to die, his death underscores the deep-rooted injustice plaguing France. Hugo writes that "[h]is gallant soul had fled," emphasizing the loss of innocent life in political uprisings against a country that would rather execute its children than listen to its people's protests.