Eunice B. Kirkman lists Mary’s birthdate as 1780, and her marriage date to John Adams as about 1795, but then she records two children born before 1795: Joshua born 15 Feb 1791 and Phoebe born about 1793. If Mary was really born about 1780, and Joshua really born in Feb 1791, then Mary would be only 10 or 11 when her first child was born. So at least one of these dates is probably off by several years. Since Eunice’s database also had “after 1860” for Mary’s date of death, it is apparent that she was aware of Mary’s appearance in the 1860 census. So what I am assuming is most likely is that Eunice made an off-by-ten subtraction error in calculating a year of birth from the age of 90 in the 1860 census. A birthdate of 1770, though, which is what would really be implied by the 1860 census, would require pushing back the estimated date of birth for Mary’s parents William Martin and Delphia Walden. So I am assuming there was a bit of rounding up in the reported age of 90 in 1860.

The 1860 census of Patrick Co., Virginia, lists Mary Banks, age 90, living with her son Roland Adams.