Pilar González de Gregorio

María del Pilar González de Gregorio y Álvarez de Toledo (born 10 January 1957), also known as Pilar Medina Sidonia, is a Spanish noblewoman, writer and socialite, who had been the former 15th Duchess of Fernandina between 1993 and 2012, until her title was revoked as a result of a legal battle with her nephew.

Her main seat of residence is at González de Gregorio Palace, in Quintana Redonda, Soria.

[2] She married, firstly, her second cousin, Rafael Márquez, 9th Count of las Torres de Alcorrín, second son of General José Joaquín Márquez y Álvarez de Toledo, 4th Duke of Santa Cristina, and María del Rosario Osorio y Díez de Rivera, 8th Countess of las Torres de Alcorrín, of the Ducal House of Alburquerque, on 16 September 1977, and divorced in 1981.

She has one child from this marriage: She married, secondly, Tomás María Terry y Merello, second son of Fernando Carlos Terry y del Cuvillo, a sherry producer from El Puerto de Santa María, of Irish descent, relative of the Cuban magnate Tomás Terry y Adán and of Blessed William Tirry, and had a second son: The Dukedom of Fernandina was rehabilitated by King Juan Carlos I of Spain in 1993, by which it was agreed on that Pilar would receive the title.

Her elder brother, Leoncio Alonso González de Gregorio, 22nd Duke of Medina Sidonia, and his eldest son, Don Alonso Enrique González de Gregorio y Viñamata, won a legal battle in order to strip her of her ducal title.