This script is for Pokémon Essentials. It displays a sixth page at pokémon summary showing a little info about the pokémon mother, father, grandmothers and grandfathers if the pokémon has any.
Doesn't work on Essentials versions older than v21.1. To see other Essentials versions, look at all branches.
Download from here and extract the contents in your root game folder. This plugin requires the Modular UI Scenes from Lucidious89.