I see thousands of sheep surrounding the dwellings of an extended Caldwell family either co-residing under one roof or in dwellings in close proximity. The dwellings likely were poorly ventilated and damp. Infection by one Caldwell could pass readily to the other Caldwells. In contrast in today's society, relatives usually do not live in close proximity and are not seen daily. The potential for Caldwell kin being wiped out today by a fatal contagious infection of one family member is much less than it would have been in medieval hamlet. To wipe out the lineage, all that is needed is to exterminate that last male issue.