Los Descendientes del Presidio de Tucson hosts an annual dinner and dance for Tucson's Birthday. Honorees are Daniel Hernandez, Jr., the congressional aide who helped save Rep.Gabrielle Giffords' life; Bill Dupont, president of the Friends of Tucson's Birthplace; and Martha Elías, Doña del Pueblo. Mariachi, a silent auction and raffle, and music for dancing round out the gala, which takes place from 5 to 10 p.m., Saturday, Aug. 27. Proceeds benefit historical and cultural preservation projects that promote Tucson history. $80. Reservations required. Call 298-7052 for reservations and more information.