"Avatar: The Last Airbender" explores the themes of family and legacy through the characters' relationships with their ancestors, their struggles with their own identities, and the impact of their choices on future generations. The show delves into the complexities of family dynamics, the importance of understanding one's heritage, and the responsibility of upholding or breaking away from familial expectations. Throughout the series, characters such as Aang, Zuko, Katara, and Toph navigate their personal histories and confront the legacies they inherit, ultimately shaping their paths and the world around them.