My gg aunt was named Sarah, born 1830 in NY, married a Silas Hatfield who died in the civil was and left her with 7 children, oldest 21, youngest 7, Silas, named after his father, year 1860. They lived in Medina, Dane, WI. Her father was Marshall Cain from MA, PA, then to WI.
This may well NOT be the lady you seek; there were a lot of Sarah's in those years.
If if looks like it fits, I have more information.