mutual affection vs sympathy

mutual affection and sympathy both are nouns.

Word	Noun	Adjective	Verb	Adverb
mutual affection	Yes	No	No	No
sympathy	Yes	No	No	No

As nouns, sympathy is a hypernym of mutual affection; that is, sympathy is a word with a broader meaning than mutual affection:

mutual affection: sympathy of each person for the other
sympathy: a relation of affinity or harmony between people; whatever affects one correspondingly affects the other

mutual affection (noun)	sympathy (noun)
sympathy of each person for the other	an inclination to support or be loyal to or to agree with an opinion
	sharing the feelings of others (especially feelings of sorrow or anguish)
	a relation of affinity or harmony between people; whatever affects one correspondingly affects the other