Northern is the opposite of Southern. Southern is related to Comfort. Comfort is related to Sympathy. 
Comfortable is related to Seat. Seat is related to Baby. Baby is related to Dad. Dad is related to Short. 
Northern <--Antonym--> Southern <--RelatedTo--> Comfort <--RelatedTo--> Sympathy 
Comfortable <--RelatedTo--> Seat <--RelatedTo--> Baby <--RelatedTo--> Dad <--RelatedTo--> Short 