In Christianity, there is no concept of a mourning period, but bereaved families often give a koden-gaeshi in a manner similar to that of Buddhism after the ascension memorial day which is held one month after the death.
キリスト教では忌中という概念はないが、死後一ヶ月後の昇天（召天）記念日のあとに仏式などに倣って香典返しを送る。