義妹[gimai] sister-in-law (younger)
兄妹げんか[kyoudaigenka] quarrel between siblings
吾妹子[wagimoko] my wife
吾妹[wagimo] my wife
姉妹会社[shimaigaisha] affiliated companies

姉妹都市[shimaitoshi] sister cities
従姉妹[itoko] cousin (female)
従妹[juumai] cousin (younger female)
弟妹[teimai] younger brother and sister
乳姉妹[chikyoudai] foster brother or sister