A woman named Helen Smith, a well known Alexander family researcher, has been to England, visiting The grave of the reverend James Alexander and his wife, Mary Maxwell. They died childless. As for the 7 brothers and 2 sisters, they probably all related but its not known if they were all brothers and sisters. I am descended from Francis Alexander, born 1654 in Rahoe county Donegal Northern Ireland. He was one of this group living in Maryland, and was the son of William Alexander who was the son of John Alexander and thats as far as I could trace. They were lowland scots who transplanted to Northern Ireland for the cheap land and this group gave rise to the name "scots Irish" Good luck with your family history