Old fashioned ‘who done it’ mysteries liked to tie up all of the loose ends. More recently there is a tendency to leave some room for doubt. The cynic might argue that this provides scope for a sequel. Family history always seems to leave unanswered questions. Dates of birth fluctuate. Names change with each census. People apparently disappear without trace. (I rule out the possibility of abduction by aliens or the idea that someone born in 1823 might still be alive!)
It would be great if a reader could say, for example “I know what happened to XXX. He ran off with the barmaid. They had two children, but never married.” Some questions will never be answered, because the records no longer exist and the remaining witnesses are long dead. Even stories from family folklore could be of some help.