mid-15c., paternite, "condition of being a father, relation of a father to a child or of God to mankind," from Old French paternité (12c.), from Late Latin paternitatem (nominative paternitas) "fatherly care, fatherhood," from Latin paternus "of a father," from pater (see father (n.)). Meaning "paternal origin, derivation from a father" is from 1868.

1520s, "process of becoming, or state of being, a son," from French filiation, from Medieval Latin filiationem (nominative filiatio), noun of action from past-participle stem of filiare "to have a child," from Latin filius/filia "son/daughter" (see filial). As "relationship of a son or daughter to a parent" (correlative of paternity) from 1794.