Long story short, I am starting small. I want to give wyverns the ability to dive. No dive bomb or anything. Wyvern_Character_BP_Base is a child of Dino_Character_BP. I have created a copy of Wyvern_Character_BP_Base and reparented it to Dino_Character_BP_DivingFlyer (which is a child of Dino_Character_BP, so nothing lost).
I am guessing that I need to bring in all the blueprints that are children to Wyvern_Character_BP_Base, even if I am not explicitly referencing them, because I cant have the base files referencing a modded file.