Mercedes was heir presumptive from her birth, but the disappointment was so great that she was initially treated only as an "infanta". Antonio Cánovas del Castillo, then head of the government, who disliked Maria Christina and did not want the crown to pass again to a female after the disastrous reign of Isabella II, decided to ignore the newborn. Mercedes's paternal aunt Isabella retained the title of Princess of Asturias until Práxedes Mateo Sagasta, President of the government replacing Cánovas, pressured King Alfonso XII to accord the title to Mercedes, which he did on 10 March 1881. On 12 November 1882, Mercedes gained a sister, Infanta Maria Teresa. The marriage of their parents was unhappy. Alfonso had married Maria Christina in order to secure the succession to the throne. He did not love his wife and was disappointed when she gave birth to two daughters, while he already had two extramarital sons. In July 1883, Maria Christina left the Spanish court and traveled with her daughters to visit her own family in Austria.