Bava Batra 114 - 1st Day of Sukkot - October 17, 15 Tishrei

If one performs a transaction with a kinyan chalipin, a symbolic act of acquiring, until what point can each side renege on the agreement? Raba and Rav Yosef differ on this point. Rav Yosef supports his opinion from the statement of Rav Yehuda regarding three who went to visit a dying person who can function as a court regarding dividing up the dying person's property. However, Raba rejects his proof. Why did the Mishna need to list the people who inherit but do not bequeath to each other, as it can be derived from the previous section of those who bequeath but do not inherit? The answer is that they wanted to teach something additional by connecting two of the three cases - a woman from her son and a woman from her husband - just as a husband does not inherit property the wife inherits after her death (property she would have inherited, were she still alive), a son does not inherit property from his mother if he is no longer alive to pass to his paternal brothers. Rabbi Yochanan quotes a statement of Rabbi Yehuda son of Rabbi Shimon that a mother inherits her son.