1) ALTERING THE INHERITANCE TO ONE'S BROTHER AMONG OTHER BROTHERS
QUESTION: The Gemara states that the Halachah follows the view of Rebbi Yochanan ben Berokah who says that one may bequeath, as inheritance, to one of his heirs (who is fit to inherit him) more property than he would receive through the normal channel of Yerushah.
The RASHBAM and TOSFOS point out that Rebbi Yochanan ben Berokah's ruling is limited to cases in which one alters the inheritance of one of his sons among other sons, or, when there are only daughters, one of his daughters among other daughters. He may not redirect the inheritance to a daughter when there are sons, or bequeath to someone else a portion when there are only daughters. This is the ruling of the TUR and SHULCHAN ARUCH (CM 381).
Does the ruling of Rebbi Yochanan ben Berokah apply only to altering the inheritance among one's sons or daughters, or also in cases when other relatives are fit to inherit him?
ANSWER: The RAMBAM (Hilchos Nachalos 6:2), when he writes that the Halachah follows the view of Rebbi Yochanan ben Berokah, adds that when a man has no children to inherit his property but rather his brothers will inherit his property, he may allot to one of his brothers a larger portion than the others, in accordance with the principle of Rebbi Yochanan ben Berokah. This is also the ruling of the SHULCHAN ARUCH (loc. cit.).
REBBI AKIVA EIGER (on the Shulchan Aruch) comments that the Rambam apparently understands the concept of sibling inheritance in the way that the BEIS YOSEF describes. The Beis Yosef (CM 253) writes that one inherits the property of his brother directly, just as one inherits from his father. The DARCHEI MOSHE (CM 253:8) disagrees and maintains that one does not inherit his brother directly. Rather, when a man dies with no children to inherit him, his estate goes to his father, and if his father is not alive, then his estate still goes to his father "in the grave," so to speak, and it is then passed to the heirs of his father (i.e. his father's other, living sons, who are the brothers of the deceased).
Rebbi Akiva Eiger suggests that had the Rambam understood the concept of sibling inheritance as the Darchei Moshe explains it, then he would not have ruled that one may alter the inheritance of his brother. According to the Darchei Moshe, the brother does not inherit him -- he is not considered "Ra'uy l'Yorsho"; rather, his father inherits him and then his brother inherits the estate from his father.
The KETZOS HA'CHOSHEN (281:2), however, asserts that it is possible that the Rambam understands the concept of sibling inheritance as the Darchei Moshe explains it. Nevertheless, the Rambam maintains that since it is the deceased person who causes the father to inherit (in his grave), which in turn causes his brother to inherit, the deceased retains the right to alter the inheritance before he dies as he chooses. (Y. MARCUS)
(The Acharonim discuss the issue of the nature of the inheritance of brothers at length. See sources cited here by the YOSEF DA'AS.)

130b----------------------------------------130b

2) REDIRECTING THE FIRSTBORN'S DOUBLE PORTION
QUESTION: The Gemara derives from the verse, "Lo Yuchal l'Vaker" (Devarim 21:16), that it is not possible to take away the double portion from the Bechor and bequeath it to another son, even though it is possible, according to Rebbi Yochanan ben Berokah, to redirect the inheritance of one son (who is not a Bechor) to another son.
Does this verse teach only that such a diversion of inheritance is not possible, or does it also teach that it is prohibited to attempt to divert the double portion from the Bechor?
ANSWERS:
(a) The RAMBAM (Hilchos Nachalos 6:3) maintains that a man who attempts to divert the double portion from his Bechor transgresses no Isur. When the Torah says, "Lo Yuchal l'Vaker," it does not mean that to do so is forbidden, but rather that the father lacks the power to do so.
(b) The RAMBAN (in his commentary to Devarim 21:16, and in his commentary to the Rambam's Sefer ha'Mitzvos, Lo Sa'aseh #12) maintains that not only does the father not have the power to do so, but it is forbidden for the father to attempt to divert the Bechor's double portion away from him. The Ramban maintains that when the verse says, "Lo Yuchal l'Vaker," it means, "You are not permitted to make the son of the beloved inherit before the son of the hated who is the firstborn," as the TARGUM ONKELUS translates the verse.
QUESTION: The KETZOS HA'CHOSHEN (251:1) challenges the view of the Ramban from the Gemara here. Rava says that Rebbi Yochanan ben Berokah's ruling (that one may alter the inheritance and redirect it to one of those who is fit to inherit him) is derived from the words, "v'Hayah b'Yom Hanchilo Es Banav" -- "And it shall be that on the day that he bequeaths to his sons" (Devarim 21:16), which implies that he has the power to cause any of his sons to inherit as he chooses. Abaye asks that the source could be the words, "Lo Yuchal l'Vaker," which imply that the father is incapable only of diverting the double portion away from the Bechor, but he may alter the inheritance of the other sons.
The Ketzos ha'Choshen asks that if the Ramban is correct and the father is not only incapable of diverting the Bechor's double portion but he is prohibited from attempting to do so, then how can the verse which teaches that he is prohibited from diverting the Bechor's double portion serve also as the source for the father's ability to alter the inheritance of the other sons? Perhaps the verse means that the father is prohibited only from attempting to divert the Bechor's inheritance, but he is not prohibited from attempting to divert the other sons' inheritance, while he nonetheless is still incapable of diverting their inheritance!
ANSWER: The Ketzos ha'Choshen answers that even according to the Ramban, had the verse intended only to teach the prohibition against diverting the Bechor's double portion, it would have said, "Lo Yevaker," and not, "Lo Yuchal l'Vaker." The added word indicates that even if he attempts to divert the Bechor's portion, his attempt is meaningless. This, however, is stated only with regard to the Bechor. Hence, it is possible to deduce from the fact that one cannot successfully divert the Bechor's double portion that one can alter the portions of any other son, as Abaye states. (Y. MARCUS)

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