1,932. When a Man Dies Before His Brother is Born
Yibum v’Chalitzah 6:16
The same is true of a widow whose husband died before his brother was born. There is no levirate bond based on Deuteronomy 25:5, “When brothers dwell together.” This is understood to mean that the brothers must be alive at the same time. The widow is prohibited to the yavam forever and she releases all of her husband’s other wives from any levirate obligation.
Yibum v’Chalitzah 6:17
Pursuant to the previous halacha, let’s say that Reuven died, leaving a widow who falls to Shimon for yibum. After Reuven died, Levi was born. Reuven’s wife is forbidden to Levi as a prohibited relation forever, regardless of whether Shimon performed yibum with Reuven's wife before or after Levi was born. Accordingly, if Shimon dies, with the result that this woman and another fall to Levi for chalitzah or yibum, neither one has a levirate bond.