In quinceañera tradition, the celebrant may give a doll to a younger sister as a symbol of childhood.
This custom is often called the changing of the doll. The doll represents the childhood that the celebrant is leaving behind as she reaches fifteen. Giving it to a younger sister can pass that childhood symbolism to the next girl in the family, although the recipient may instead be another young relative.
The ritual is an optional tradition, not a universal requirement. Some families use a porcelain doll, a keepsake doll, or another symbolic gift. Others omit the custom entirely or replace it with a different presentation. The details can vary by country, region, family, and generation.
The doll ceremony is separate from the changing of shoes. In the shoe ritual, a father or another family member may replace flat shoes with high heels. Both customs symbolize transition, but they use different objects and have different meanings.