Emergency is related to Reserve. 
Chill is related to Cold. Cold is a different concept from Fever. Fever can cause/lead to Headache. one thing you do when you Contemplate is Headache. 
Emergency <--RelatedTo--> Reserve 
Chill <--RelatedTo--> Cold <--DistinctFrom--> Fever --Causes--> Headache <--HasSubevent-- Contemplate 