OPINIONS: The Mishnah discusses several cases in which a Ketanah and her Tzarah fall together to Yibum, and the Yavam lives with both of them (or he and his brother each take one of them). The Mishnah concludes with the view of Rebbi Elazar who states that Beis Din instructs the Ketanah to do Mi'un, because by doing Mi'un she prevents her Tzarah from becoming forbidden to the Yavam.

According to the Girsa of the Rif and other Rishonim, Rebbi Elazar says that "in all of the cases (b'Chulan) Beis Din instructs the Ketanah to do Mi'un." Does Rebbi Elazar actually argue that in all of the cases of the Mishnah the Ketanah should do Mi'un? The Mishnah discusses not only cases of a Ketanah and a Gedolah who are Tzaros, but also cases of a Ketanah and a Chareshes who are Tzaros. In the case of a Yavam who lived with both the Ketanah and the Chareshes, does Rebbi Elazar also maintain that Beis Din instructs the Ketanah to do Mi'un so that the Chareshes will not be forbidden to the Yavam?

(a) The RA'AVAD on the Rif and on the Rambam (Hilchos Yibum 5:24) writes that Beis Din does not instruct a Ketanah to do Mi'un when her Tzarah is a Chareshes. He explains that the reason why Beis Din would instruct a Ketanah to do Mi'un is "Gedolah Ramya Kamei" -- by doing Mi'un, the Ketanah enables the Gedolah to fulfill her Chiyuv d'Oraisa of Yibum. In contrast, a Chareshes has no Chiyuv d'Oraisa to do Yibum, and therefore there is no reason to instruct the Ketanah to do Mi'un.

(b) The RAMBAN and other Rishonim disagree with the Ra'avad. The Ramban writes that the only reason the Gemara (109b) gives for why a Ketanah should "distance herself from Mi'un" is that after the Ketanah reaches adulthood she may regret having done Mi'un and she will be left without a husband. In the case of the Mishnah, however, the Yavam lived with the Chareshes after he lived with the Ketanah, and thus the Ketanah becomes forbidden to the Yavam in any case (and she must do Chalitzah and receive a Get if she does not do Mi'un). Therefore, there is no point in discouraging her from Mi'un.

Why, then, does the Gemara state that one would have thought that Rebbi Elazar's ruling applies only in the cases of the earlier Mishnah (109a) and not in the cases of the Mishnah here, or that it applies only in the cases of the Mishnah here but not in the cases of the earlier Mishnah? It is unreasonable to suggest that his ruling applies only in the case of the Mishnah here and not in the previous Mishnah, in which the sister of the Ketanah who does Mi'un falls to Yibum to the Ketanah's husband. In all of the cases, if the Ketanah does not do Mi'un she will be sent away with a Get, and thus Beis Din certainly should instruct her to do Mi'un. Moreover, why does the Tana Kama argue with Rebbi Elazar in these cases?

The RAMBAN explains that in the case of the Mishnah here, perhaps the Yavam should be penalized for living with the Chareshes (when he was prohibited to do so) after he lived with the Ketanah, and that is why the Ketanah should not be allowed to do Mi'un. In the case of the earlier Mishnah, it may be preferable not to instruct the Ketanah to do Mi'un so that her sister will not fall to Yibum after her Mi'un. If her sister falls to Yibum after her Mi'un, it will appear as though the Yavam is marrying "Achos Ishto," the sister of his wife (since not everyone will realize that the Ketanah did Mi'un).

Therefore, when a Ketanah and Chareshes fall together to Yibum, and the Yavam does Yibum with the Ketanah and afterwards he lives with the Chareshes, the Ketanah should do Mi'un to retroactively remove her Zikah to Yibum and thereby permit the Chareshes to the Yavam.

(c) The RAMBAM (Hilchos Yibum v'Chalitzah 5:28) rules that if the Yavam lived with the Chareshes and then with the Ketanah, Beis Din does not instruct the Ketanah to do Mi'un and to uproot the Zikah of Yibum from herself, thus leaving the Chareshes as the only Yevamah, as the Ramban writes. However, the Rambam adds that even after the Ketanah does Mi'un, the Yavam should divorce the Chareshes with a Get.

The RAMBAN, RASHBA, and other Rishonim are perplexed with this ruling. If the Ketanah retroactively is not a Tzarah of the Chareshes (because of her Mi'un), why does the Yavam need to divorce the Chareshes with a Get?

One might answer that the Mi'un of the Ketanah does not help to permit the Chareshes to the Yavam because at the time she fell to Yibum it certainly looked like the Ketanah was also a Yevamah. Therefore, the Rabanan enacted that the Yavam's Bi'ah with the Ketanah renders the Chareshes Pesulah even after the Ketanah's Mi'un. This answer is untenable, however, because the Rambam himself (ibid. 5:30) writes that in a case in which the Yavam lived with a Ketanah and then with a Gedolah, the Ketanah should do Mi'un so that the Gedolah retroactively becomes the only Yevamah and becomes permitted to the Yavam! If Mi'un does not completely permit the other Yevamah (as in the case of the Chareshes), the Rambam should say that the Gedolah is not permitted, because she became Pesulah through the Yavam's Bi'ah with the Ketanah that preceded his Bi'ah with her.

The Rishonim reject the ruling of the Rambam because of this problem.

The VILNA GA'ON (EH 171:13) points out that the Rambam himself answers this question. The Rabanan indeed enacted that Bi'ah with the Ketanah before Mi'un renders the Chareshes Pesulah, as mentioned above. However, in the case of the Gedolah and Ketanah, where the Yavam lived with the Ketanah and then with the Gedolah, the Yavam may remain with the Gedolah because, as the Rambam writes, the Kinyan of the Gedolah is a "Kinyan Gamur" (a Kinyan d'Oraisa). The Rabanan did not enact that Bi'ah before Mi'un disqualifies a "Kinyan Gamur." It can disqualify only a Kinyan which is not complete (a Kinyan d'Rabanan), such as the Kinyan of a Chareshes.