“ The Lat. consobrinus, which has given “cousin,” is from con-sobrinus, sosbrinus, from the stem of soror, sister. As “brother” and “brethren” are used for the male members of a religious body or community, so also is “sister” for the female members; more particularly it is applied to the members of a female religious order or community, a “sisterhood,” in the Roman and other churches, who are devoted to a religious life, works of charity or mercy, whether bound by irrevocable vows or not. ”