Hi ELizabeth, Here is what I know about Robert Henry Prettyman.Hope you find it helpful.
1.ROBERT HENRY PRETTYMANwas born Aft. 1763, and died June 17, 1851.He married AMELIA (MALLEE) REDDEN Abt. 1790, daughter of STEPHEN REDDEN and MARY REDDEN.She was born Abt. 1770 in Somerset County, Maryland, and died Bef. 1854.
Children of ROBERT PRETTYMAN and AMELIA REDDEN are: i. SARAH PRETTYMAN, b. Abt. 1795; d. 1813, Sussex County, Delaware. ii. ROBERT PRETTYMAN, d. June 17, 1851; m. MARY (HYATT) SHANKLAND; d. March 07, 1862. iii. WILLIAM PRETTYMAN, b. December 15, 1793, Sussex County, Delaware; d. July 07, 1877, Mispillion Hundred, Kent County, Delaware; m. (1) LAVINIA S. CANNON, February 20, 1827, Sussex County, Delaware; b. 1808; d. May 07, 1879; m. (2) EDNEY ENHANCE DOWSON, May 03, 1821. iv. BURTON R. PRETTYMAN, b. Abt. 1793, Medford, Delaware; d. Aft. 1861, Berrein Co, MI.; m. (1) NANCY BUTLER, Bet. 1812 - 1817, Delaware; b. 1792; m. (2) PRUDENCE MAJORS; b. Abt. 1807, Delaware; d. Aft. 1850, Missouri.