These McKees aren't my ancestors, but I found them while looking up other Co. Monaghan families.
from "Biographical and Historical Catalogue of Washington and Jefferson college" (1902)
McKee, David. — Son of David and Jane (Smith); born Ballibay, County Monaghan, Ireland, April 10, 1821; Theology Center and Northwood Theological Seminary; Professor of Greek, Western College (now Geneva College), '51-54; licensed April 9, '51, Presbytery of Pittsburg; ordained July 5, '54; Presbytery of Philadelphia; Moderator of Synod; pastor Philadelphia, Pa., '54-59, Clarinda, la., '62-93; married, '56, Mary E., daughter of David Gregg; died near Clarinda, la., Dec. 27, '93. Reformed Presbyterian minister.