1,936. Three Brothers, Two Married to Sisters

Yibum v’Chalitzah 6:24

If the yavam performed yibum with the other widow because he thought that the one forbidden as a prohibited relation was congenitally infertile but it was subsequently found that such was not the case, he must give a get to the one with whom he performed yibum. Any children that may have been produced by this union are illegitimate.

Yibum v’Chalitzah 6:25

Let’s say that there are three brothers, two of whom are married to sisters, and one of whom is married to an unrelated woman. If the brother married to the unrelated woman died, and then one of the brothers married to the sisters died, the surviving brother should perform chalitzah and not yibum with the unrelated woman. This woman had a levirate bond to the second brother, whose wife is the sister of the remaining brother’s wife. Even if one of the brothers married to sisters divorced his wife after the brother married to the unrelated woman died, and then he died, the surviving brother should only perform chalitzah and not yibum with the unrelated woman. This is because there was a brief period when this woman had a levirate bond to the second brother while his wife was the sister of the surviving brother’s wife. If he were to perform yibum with her, one might come to perform yibum with a woman in such circumstances even when the second brother didn’t divorce his wife.