fraternal

By Cognate or Domestic duties, we mean those which grow out of the different family relations; and which may be classed as conjugal, parental, filial, and fraternal.

The changing Afro-American class structure shaped the war and postwar growth of black religious and fraternal organizations in southern West Virginia.

[…] a delighted shout from the children swung him toward the door again. His sister, Mrs. Gerard, stood there in carriage gown and sables, radiant with surprise. ¶ "Phil! You! Exactly like you, Philip, to come strolling in from the antipodes—dear fellow!" recovering from the fraternal embrace and holding both lapels of his coat in her gloved hands.

Seventy percent of twins are fraternal and result from fertilization of two separate ova by two different sperm.