kinship vs family relationship

kinship and family relationship both are nouns.

Word	Noun	Adjective	Verb	Adverb
kinship	Yes	No	No	No
family relationship	Yes	No	No	No

As nouns, kinship and family relationship are synonyms defined as:

kinship and family relationship: (anthropology) relatedness or connection by blood or marriage or adoption

Other synonyms of kinship include relationship.

kinship (noun)	family relationship (noun)
(anthropology) relatedness or connection by blood or marriage or adoption	(anthropology) relatedness or connection by blood or marriage or adoption
a close connection marked by community of interests or similarity in nature or character