THESAURUS
Son
aunt, auntie, blood brother, brethren, brother, bub, bubba, bud, buddy, child, country cousin, cousin, cousin once removed, cousin twice removed, daughter, descendant, father, first cousin, foster brother, foster child, frater, grandchild, granddaughter, grandnephew, grandniece, grandson, granduncle, great-aunt, great-uncle, half brother, heiress, junior, kid brother, lad, laddie, mother, nephew, niece, nuncle, nunks, nunky, offspring, scion, second cousin, sis, sissy, sister, sister-german, sistern, son and heir, sonny, stepbrother, stepchild, stepdaughter, stepsister, stepson, stripling, tad, unc, uncle, uncs, uterine brother
ROGET THESAURUS
Son
Posterity
N
posterity, progeny, breed, issue, offspring, brood, litter, seed, farrow, spawn, spat, family, grandchildren, heirs, great-grandchild, child, son, daughter, butcha, bantling, scion, acrospire, plumule, shoot, sprout, olive-branch, sprit, branch, off-shoot, off- set, ramification, descendant, heir, heiress, heir-apparent, heir- presumptive, chip off the old block, heredity, rising generation, straight descent, sonship, line, lineage, filiation, primogeniture, filial, diphyletic, the child is father of the man, the fruit doesn't fall far from the tree, like father, like son.