Cecilia was born in El Pardo (Madrid's district and municipality) in 1948. Her father, José Ramón Sobredo, was a military officer and diplomat. During her childhood she lived in other countries such as the United Kingdom, the United States, Portugal, Algeria and Jordan. She learned to speak English in addition to her native Spanish language. Her first few works were in English, but the rest were in Spanish. She studied music at a convent school in the United States. A nun taught her to play the guitar. When she returned to Spain she attended law school, but left her studies in order to work in the music industry.