Casualty is related to Wound. Wound is related to Bite. Snap is a type of Bite. Snap is related to Cookie. 
Retired is derived from Retire. Retire is related to Rest. Rest is related to Free. 
Casualty <--RelatedTo--> Wound <--RelatedTo--> Bite <--IsA-- Snap <--RelatedTo--> Cookie 
Retired --DerivedFrom--> Retire <--RelatedTo--> Rest <--RelatedTo--> Free 