Question: At what age did the Mexican actress, singer and model appear on "Tu y Yo" with the 1978 winner of Miss Costa Rica?
Sentence (from "Maribel Guardia"): Maribel Guardia (] ; born Maribel del Rocío Fernández-García on 29 May 1959 in San José, Costa Rica) is a Costa Rican actress, model, singer and TV hostess.
Relevant evidence: No