She was born circa 1776. Her father was Jose Cosme de la Garza, and her mother was Maria Josefa de la Peña.
In 1782, she lived in San Nicolas/ Santa Rosalia de la Bonita in household number 140. The church census recorded that she was a young child, española, and 6 years old. Her household included 3 people:
Jose Cosme de la Garza, married, español, age 26.
Maria Josefa Peña, married, española, age 20.
Maria Tomasa de la Garza, a young child, española, age 6.