According to the "Southern Campaign, American Revolution Pension Statements & Rosters" Pension application of John Dysart, P-152148, we learn the fate of James, his father, and William, his brother. John was the son of James Dysart, P-152144. James was born in 1727 in New Londonderry, Ireland, and immigrated to the American Colonies. While living in Chester County, Pennsylvania, John was born December 25, 1749; William, P-152149, in 1751, while Mary Elizabeth and James Y. S. Dysart followed.  

In 1776, John Dysart volunteered and served to guard the North Carolina frontiers from the Cherokee Nation warriors. John was engaged as a volunteer multiple times in the following years, and in 1780, he was engaged in a losing battle at Cane Creek in Burke County, North Carolina, to Patrick Ferguson and his troops. The Americans retreated over the Blue Ridge Mountains to the Holston River. In late September of 1780, they joined Colonels William Campbell, John Sevier, and Isaac Shelby there. With eleven hundred men, the group that became known as the Over Mountain Men went on to King's Mountain, where they fought and defeated Ferguson on October 7, 1780.

In 1781, John volunteered to pursue Cornwallis in his march from Charlotte, North Carolina, to Salisbury in Rowan County, North Carolina. General Nathanael Greene, in his "Race to the Dan," as this was called, ordered General William Lee Davidson to slow the British Army's crossing of the Catawba River. Early in the morning of February 1, 1781, the British moved down to "force a passage" at Cowan's Ford, a private ford guarded only by Lieutenant Thomas Davidson with twenty-five men. General Davidson rallied several hundred patriots to battle the British there, and for a few minutes, the action was lively. The militiamen were picking off many British soldiers struggling in the water. Once the British established themselves across the river, their return fire became heavy. Hardly had Davidson arrived when he was struck from his horse. Three other Americans were killed in a few minutes, and the patriots retreated. Unfortunately, James and William Dysart, father and son, were among the dead. 

The battle occurred about twelve miles from James and Margaret Dysart's home. Margaret, her daughter Mary Elizabeth, and her son James Y. S. Dysart could hear the battle begin with small arms fire echoing in the distance. After the battle of Cowan's Ford, searchers found General Davidson's dead body stripped naked by the British. His friends and wife buried him, James, William, and the other patriot hastily by torchlight five miles away at Hopewell Presbyterian Church. The British lost over 100 soldiers. The Americans lost four. The Dysart family accounted for half of the losses.