María del Socorro Sánchez del Rosario was born on 15 August 1830 on the island of Hispaniola, in Santo Domingo, which at the time was part of the Republic of Haiti, to María Olaya del Rosario de Belén and Narciso Sánchez Ramona. Her father descended of slaves and her mother was a free woman of color, descended of European and African ancestors. Her father's sister María Trinidad Sánchez, was executed for her participation as a freedom fighter in the Dominican War of Independence. Her mother was a hairdresser and made combs, while her father worked in the meat trade, selling, butchering and raising cattle. Sánchez was one of eleven siblings: Francisco (1817–1861); Tomás (1819–1878), Eugenio (1822–1889); Manuel de Jesús (1823–?); María de la Cruz (1824–?); Juan Francisco (1826–1845); Jacinto (1827–1900); Pablo Marcial (1829–?); Ana (1832–?); and Idelfonso (1834–1897). Francisco is recognized as one of the co-founding fathers of the Dominican Republic.