My 4th great grandmother Rebecca Anderson is on the 1850 census living with son Preston Anderson and family in Blandinsville Township of McDonough County Illinois. Preston and family came to Illinois in 1843 from White County, Tennessee. He and family are buried in Anderson Huff Cemetery just east of Blandinsville. A stone next to Preston and his wife Lieurana Duncan Anderson has the name broken off but shows words "wife of P. Anderson 4 Sep 1864". This may be Rebecca but I cannot find her on the 1860 Census nor in any death record. Can anyone help me?