From Familypedia

The category lineage contains pages with agreed lines of descent between key people.

A lineage can be included in any page by transclusion. For example, the text {{:Lineage from William the Conqueror to Henry II}} would display William, William's son Henry, his granddaughter Matilda and his great-grandson Henry. See for instance Catharina-Amalia van Oranje-Nassau (2003)/Ancestors.

The main advantage is that information is stored at one place only, and that edits are transmitted automatically. Technically, lineages modularise lines of descent.

For this to work at many pages, it is important that there is no title at the lineage page.