Zapotan is in Jalisco state. I just checked on FamilySearch.org and they have baptismal records for the parish of Zapotan dating back to 1637 online...so it should not be hard to verify her date of birth (assuming her parents had her baptized).
I worked as a claims rep for Social Security back in the early 70s.
Baptismal Records were one of the common tools we used to establish age. I was also surprised at just how good Mississippi Black School records were for just after 1900.