Elizabeth Farmer 1807 of PA, VA, or OH

Looking for birthplace information on Elizabeth FARMER.  Hoping to find a record leading to information on her parents.

Elizabeth FARMER b 20 August 1807 d 22 January 1875 Blandinsville, Illinois, US

Married 12 December 1833 Robert Parks CHAPIN (b 12 May 1810)

Married 27 March 1853 Almon Barrett STEEL (b 10 February 1808)

Find a grave lists her birthplace as Pennsylvania.  The death certificate of her first husband, Robert Parks CHAPIN, lists her birthplace as Ohio.  Elizabeth C WALDRON, granddaughter, was the informant.  Federal 1860 Census lists her birthplace as Ohio.  Federal 1850 Census extraction lists the birthplace as Virginia.  I have examined the 1850 census and the birthplace is not Ohio, as it doesn't match the birthplace of her children. 

Any additional information on her birthplace, birth record, or any sources indicating her parents would be appreciated.