Kid is related to Class. Class is related to Room. Room is related to Location. Location is related to Tree. 
Companion is a type of Traveler. Companion is a synonym of Associate. Participant is a type of Associate. 
Kid <--RelatedTo--> Class <--RelatedTo--> Room <--RelatedTo--> Location <--RelatedTo--> Tree 
Traveler <--IsA-- Companion <--Synonym--> Associate <--IsA-- Participant 