68:6.8
The early races often resorted to practices designed to restrict population; all primitive tribes killed deformed and sickly children. Girl babies were frequently killed before the times of wife purchase. Children were sometimes strangled at birth, but the favorite method was exposure. The father of twins usually insisted that one be killed since multiple births were believed to be caused either by magic or by infidelity. As a rule, however, twins of the same sex were spared. While these taboos on twins were once well-nigh universal, they were never a part of the Andonite mores; these peoples always regarded twins as omens of good luck.