Can you name all eight of your great-grandparents? Do you know what they did for a living? How about where they lived? Recent research has revealed that over five million of us know nothing about our great-grandparents. Although most people know a lot about their grandparents, just 10% of Brits know basic details about their great-grandparents, such as their names, birthplaces, and occupations. News of this generational knowledge gap is worrying - it reminds us of the importance of researching and preserving…