Ancestor highlighting is accessed through a pulldown menu next to the Zoom box (above the pedigree display). It is included in Pedigree Assistant version 3.21 or later. The following options are available:
This will highlight any ancestors which are present more than once in the displayed pedigree.
Specifically, Pedigree Assistant locates each ancestor that occurs twice or more within the displayed generations, and highlights each with a unique colour.
Similar to the 'Repeat Ancestors' option but only ancestors which are present on both the sire and dam sides of the pedigree are highlighted. Common ancestors are those that give rise to inbreeding.