Union is a type of Device. Device is related to Toy. Toy is related to Christmas. Christmas is related to Marry. 
Skin is a type of Layer. Skin is etymologically related to Shed. 
Union --IsA--> Device <--RelatedTo--> Toy <--RelatedTo--> Christmas <--RelatedTo--> Marry 
Layer <--IsA-- Skin --EtymologicallyRelatedTo--> Shed 