1,951. When We Don't Know Which of Two Sisters Was Betrothed
Yibum v’Chalitzah 8:1
Let’s say that a man betroths one of two sisters but he doesn’t know which one, and he dies. If he has one brother, that brother should perform chalitzah with both sisters in order to free them to marry other men. If he has two brothers, one of them should perform chalitzah with one of the sisters, after which the other brother should perform yibum with the other sister. If the woman he marries was the one betrothed by the deceased brother, then he has performed yibum with her; if she isn’t the one his brother betrothed, then he has simply married a woman, chalitzah already having been performed by her sister, whom the late brother had betrothed. We don’t perform yibum first in such a case because of the possibility that the other woman is the one whom the late brother betrothed. If this is the case, then the surviving brother will have married a relative of the woman to whom he has a levirate bond. If the brothers act on their own volition, without seeking guidance, and each of them marries one of the sisters, these couples are not forced to separate.
Yibum v’Chalitzah 8:2
Let’s say that two (unrelated) men, each of whom has a brother, betroth two sisters, and they don’t know which of them has betrothed which sister. If both of these men die, each one’s brother should perform chalitzah with both sisters. If one of the men had one brother and the other had two brothers, then the one brother should perform chalitzah with both sisters, after which one of the two brothers should perform chalitzah with one sister and the other brother should perform yibum with the other. If these brothers act on their own volition, without seeking guidance, and each of them marries one of the sisters, these couples are not forced to separate. This is so even if the brothers are kohanim. While there’s a rabbinic enactment prohibiting a kohein from marrying a woman who has performed chalitzah, the women in this case only performed chalitzah out of doubt. The Sages didn’t enact this prohibition in a case where chalitzah was performed out of doubt.