The youngest sister of Spain?s Princess Letizia has died in Madrid at 31, the Royal Palace said recently.

The cause of Erika Ortiz?s death was not immediately revealed. Letizia?s family issued a statement asking for ?prudence and respect? in relation to the death. Ortiz was the sister of Letizia, who married Crown Prince Felipe, heir to the Spanish throne in 2004. They have a 1-year-old daughter, Princess Leonor, and Letizia is pregnant with her second child and due to give birth in May. Queen Sofia interrupted a trip to Indonesia on hearing of the death, the palace said. Spanish National Radio said the queen was in tears as she explained to reporters that she would return to Spain. King Juan Carlos was in Germany and was due to return to Spain later. A graduate in fine arts, Ortiz was the youngest of three daughters of journalist Jesus Ortiz and Paloma Rocasolano, a nurse. Princess Letizia is the eldest. Ortiz worked at the Spanish production company Globomedia. She was married to Spanish sculptor Antonio Vigo and had a 6-year-old daughter, Carla.