you are likely to find Show in/at/on Opera. 
Grandfather is a type of Grandparent. Grandfather is related to Relative. Cousin is a type of Relative. Cousin is the opposite of Sibling. 
Opera <--AtLocation-- Show 
Grandparent <--IsA-- Grandfather <--RelatedTo--> Relative <--IsA-- Cousin <--Antonym--> Sibling 