Study Yevamot folio 10B with parallel Hebrew-English text, traditional commentary, and modern study tools. Free access to Babylonian Talmud online.
If, however, his mother was a woman who was raped by his father and subsequently married his paternal brother, and the brother died, this is a case of his mother who exempts her rival wife. According to the opinion of the Rabbis this marriage is permitted, and even according to the opinion of R' Ye
And although A baraita states in the Mishnah: 15 women, we must add a 16th case, for example, the situation described above. Reish Lakish said to R' Yoḥanan: According to the opinion of Levi, who said that the Mishnah teaches even cases of: What if, which involve a transgression, let the Mishnah a
R' Yoḥanan said to Reish Lakish: This example is not cited because the case does not include the possibility of a rival wife of a rival wife. All of the other cases listed in the Mishnah involve both rival wives and rival wives of rival wives. Here, however, this is impossible, as the same prohibit
The Talmud asks: And let R' Yoḥanan say a different answer to Reish Lakish, as he could simply have pointed out that marriage to a woman who had performed ḥalitza is not a violation that incurs karet, neither for the one who performed the ḥalitza nor for his brothers if they marry her after he dies.
The Talmud responds that R' Yoḥanan is speaking in accordance with the statement of Reish Lakish, as follows: According to my opinion your question is groundless, as they are liable for violating a prohibition, and those liable for violating a prohibition are obligated in ḥalitza and levirate marria