Mary Kinkaid was born in 1763 in Middleton, Cumberland, Pennsylvania. She was married to Mathew McClaren in 1780 at the age of 17. They had seven children: Catherine, Jane, Mary, George W. (b. September 9, 1796), Susannah (b. February 2, 1798), Nancy (b. 1800), and James (b. January 11, 1807).