kindred n.

c. 1200, from Old English cynn "family; race; kind, sort, rank; nature" (also "gender, sex," a sense obsolete since Middle English), from Proto-Germanic *kunja- "family" (source also of Old Frisian kenn, Old Saxon kunni "kin, kind, race, tribe," Old Norse kyn, Old High German chunni "kin, race;" Danish kjön, Swedish kön, Middle Dutch, Dutch kunne "sex, gender;" Gothic kuni "family, race," Old Norse kundr "son," German Kind "child"), from PIE root *gene- "give birth, beget," with derivatives referring to procreation and familial and tribal groups.

In the Teutonic word, as in Latin genus and Greek [genos], three main senses appear, (1) race or stock, (2) or kind, (3) gender or sex .... [OED]

Related to both words kind and to child. From 1590s as an adjective, from the noun and as a shortening of akin. Legal next of kin (1540s) does not include the widow, "she being specifically provided for by the law as widow" [Century Dictionary], and must be a blood relation of the deceased.

word-forming element meaning "condition or state of," Middle English, from Old English -rede, from ræden "condition, rule, reckoning," a suffixed form of ræd "to advise, rule" (see rede). Common in Old English, less so in Middle English but still active in word-formation. It is analogous to -hood, which has replaced it in brotherhood, neighborhood, etc.; it survives in about 25 words.