She was born circa 1774. Her father was Juan Eligio Casas, and her mother was Maria Rosalia Olivares. Her father owned Camargo 39 grant.
In 1782, she lived in San Juan Bautista del Cojo in household number 130. The church census recorded that she was a young child, casta, and 8 years old. Her household included 4 people:
Juan Eligio Casas, married, casta, age 33.
Maria Rosalia Olivares, married, casta, age 30.
Maria Josefa Casas, a young child, casta, age 4.
Maria Leonarda Casas, a young child, casta, age 8.