Current schema such as GEDCOM, which is the most widely used standard in genealogy don’t have a single underlying concept to help govern how the data is represented, despite that the goal is usually the very special case of a graph that is a hierarchical family tree.

A problem with the family tree model itself is that it is not fault tolerant, and in order to join different people’s family trees together they need to allow for changes (e.g. finding that the father of someone is not who was originally thought). The edge labelled graph of events allows for the events to be weighted according to evidence, and a family tree to be rendered based on that.