Philip Prospero, Prince of Asturias

Philip Prospero of Austria, Prince of Asturias (Felipe Próspero José Francisco Domingo Ignacio Antonio Buenaventura Diego Miguel Luis Alfonso Isidro Ramón Víctor; 28 November 1657 – 1 November 1661) was the first son of Philip IV of Spain and Mariana of Austria to survive infancy. Philip IV had no male heir since the death of Balthasar Charles, his son by his first wife, Elisabeth of France, eleven years before, and as Spain's strength continued to ebb the issue of succession had become a matter of fervent and anxious prayer.