The story uses physical size as a metaphor for growing up. The younger sister isn't just taller; she’s more confident, taking up more space in the room and in conversations. The narrator has to learn how to navigate a world where they are no longer the "big" sibling, finding a new identity that isn't based on being the largest person in the house.
She had turned my humiliation into a service agreement. my younger sister is taller and stronger than me stories
"Deal," she said, patting me on the back—hard enough to make me stumble forward slightly. The story uses physical size as a metaphor for growing up