Elderly is the opposite of Young. Young is related to Son. Son is related to Comparison. 
Ambassador is related to Other. Other is similar to New. New is related to Birthday. Birthday is related to Eat. 
Elderly <--Antonym--> Young <--RelatedTo--> Son <--RelatedTo--> Comparison 
Ambassador <--RelatedTo--> Other <--SimilarTo--> New <--RelatedTo--> Birthday <--RelatedTo--> Eat 