"Sarah (Gaines), b. 23 Mar. 1704; d. unm. in 1770. Her will, dated 2 Oct. 1753, contains proof of the marriages of her two sisters."
There is no accessible evidence to support either a death in 1770 or that she died unmarried. If she died in 1770, and was the second wife of John Hall, she would have died a widow. Examination of the record of her probate would be helpful.