James Galbraith of Balgair and his wife, Mary Buchanan, had at least four sons and a possible daughter. The sons of James Galbraith of Balgair were James, Robert, Humphrey, and William. The first three were well known, well respected, and well documented in various accounts and histories of Donegal in the 1600s. These Galbraiths were a leading Donegal family at that time. James served twice as a Member of the Irish Parliament and later as a Lt. Col. in the Lagan Army, which was a military force of Scottish immigrants in Donegal, mobilized to confront the Catholic Irish uprising in 1641, and which later fought a losing battle against the forces of Oliver Cromwell and Parliament. Robert was also a Lt. Col. in the Lagan Army. (There is a possibility that both James and Robert had previous military service fighting in the Thirty Years War on the Continent and were accorded high rank in the Lagan Army because of it.) Humphrey served as a minister in the Church of Ireland, an Anglican church, and rose to the senior position of Archdeacon. There are only a few references to William in the historical record and we know little about him, except that he is explicitly referred to as a brother to the others.
James had four daughters. Robert had two sons and two daughters: one son died young. The other son was James Galbraith of Ramoran, another Galbraith who served a term in the Irish Parliament. James of Ramoran had three daughters. His uncle, Humphrey, had three daughters. There were no sons in the historical record to continue the line.
With respect to the possible daughter, the will of James of Ramoran, son of Robert Galbraith of Dowish, refers to an uncle, Thomas Lucy. We know nothing of any Lucys in Galbraith history; Thomas Lucy must have been married to James of Ramoran's aunt, whose given name is unknown. That aunt could have been a sister of his father's, and sister to the other Galbraith brothers, or she could have been a sister to his mother, Jean Cunningham. We do not know the Cunningham genealogy. At any rate, there has so far been discovered no further reference to this aunt, the wife of Thomas Lucy
The 1718 Galbraiths were clearly a leading and well respected family when they arrived in Pennsylvania. They were elected to the colonial assembly and to such other positions as sheriff, justice of the peace, and coroner. They helped to found the Donegal Church, served as elders at that church, and represented their church at meetings of the Donegal Presbytery. If the important 1718 Pennsylvania Galbraiths were descended from that leading Donegal Galbraith family, how did that occur?