The traditional last-doll gift presented to a quinceañera is a doll.
The doll symbolizes the celebrant leaving childhood behind as she reaches her fifteenth birthday. It is often presented by a parent or another close relative during the reception, although the timing and ritual differ among families.
The custom is symbolic rather than mandatory. Some families replace the doll with another meaningful object, while others omit the ritual entirely. The important idea is the contrast between childhood and the responsibilities associated with growing older.
The last doll can be confused with other quinceañera symbols, such as the changing of shoes or the presentation of a tiara. Those are separate customs, and no single ceremony includes every possible tradition.