Jane,
I sent you an email a couple of days ago along with an invitation to look at my tree. Maybe it was sent to your spam folder?
I was trying to warn the other poster, Sarah, that the McCombs line from South Carolina that you are researching is not directly related to our line of McCombs, who lived in Harrison County, Ohio, about 200 years ago and then moved to Marion County, Iowa, shortly after the Civil War. (I recognize Sarah's screen name. She's in my line of McCombs.)
There is a huge mistake in the One World Tree that somehow connects your family in South Carolina and our family in Ohio because the surname is the same. It sends my family veering off from Ohio to South Carolina in the very early 1800s and late 1700s. But there is no evidence that shows that our two lines are directly connected or that any of my McCombs family members ever lived in South Carolina in the 1700s or earlier. If Sarah will look more closely at your earlier posting with the names of the children, their spouses, dates of birth and death, then she would see that none of it matches up with our tree. The only match is the name "McCombs." Moreover, our John and Margaret McCombs died in Harrison County, Ohio. Your John and Margaret McCombs died and are buried in South Carolina. Everyone in my family tries to highjack your John and Margaret and make them our great grandparents and adds your Abbeville, SC, relatives to our tree.
I sometimes get mad and frustrated when people duplicate this error from the One World Tree. Half of my immediate family members who are into genealogy have made this link and have repeated this error in their trees and they're running around thinking that their 7th great grandfather was living in Abbeville, SC, in the 1700s. (I even fell for this for awhile until I did more research.) I've tried to warn people in my family, but they usually get mad and frustrated with me. But it's true. Our immediate line of McCombs cannot be traced back any further than the very early 1800s in Ohio. (I would love to take my tree further and add more geneations but I know that it doesn't pass through South Carolina. My McCombs family was probably in either Washington County, Pennsylvania, or Baltimore, Maryland, in the 1700s.)