THESAURUS
blood brother
aunt, auntie, brethren, brother, bub, bubba, bud, buddy, country cousin, cousin, cousin once removed, cousin twice removed, daughter, father, first cousin, foster brother, frater, grandnephew, grandniece, granduncle, great-aunt, great-uncle, half brother, kid brother, mother, nephew, niece, nuncle, nunks, nunky, second cousin, sis, sissy, sister, sister-german, sistern, son, stepbrother, stepsister, unc, uncle, uncs, uterine brother