Here are some stuff that might be useful or just fun to have:
One-Roll Monster Generator : There are rules in the main book to create monsters using the typical ORE roll, this way it’s automated!
ORE Basics : Monsters uses Stolzes’ ORE system. If you’re not completely clear how it works or need a refresher, this is a nice and quick explanation.
Character Sheets : These are the character sheets for your kid and your monster, in case you want a physical copy.