I know James was the youngest of the brothers. The next youngest was William. He died on August 4, 1774. John McCullough was born about 1715 so I can see the possibly of who you're talking about being his children. The names John, Hugh, and William come up a lot in my family. Each generation has a couple of each name. Joe Thomas McCullough of Ocala, Florida has researched John's side more. Mine comes from Hugh and I know he had sons named John (born 1777), Hugh (born October 2, 1780), William (born March 6, 1783), Andrew (born December 25, 1785), and Alexander (January 1, 1788). Sadly I have very little knowledge of any of Hugh's children except Alexander's and know hardly anything about Hugh's brothers' families. But this December I will have a lot more free time to do research and will be going to Williamsburg, SC to do research. I will definately keep you posted. I'm from Georgetown so a lot of the records are fairly close as it is.