Juana Enriqueta Josefina de los Sagrados Corazones Fernández Solar was born in 1900 in Santiago in Chile the upper class Miguel Fernández and Lucia Solar as the fourth of six children; three males and two females not including herself. Her brothers were Luis and Miguel and Ignacio and her sisters were Lucía and Rebeca (d. 31 December 1942). Rebeca became a Discalced Carmelite nun at the same convent as Juana as "Teresa of the Divine Heart". Her mother was Lucía Solar de Fernández, her father was Miguel Fernández Jara and her maternal grandfather was Eulogio Solar. Her baptism was celebrated in the parish church of Santa Ana.