Commentary for Bava Batra 9:3
הִנִּיחַ בָּנִים גְּדוֹלִים וּקְטַנִּים, הִשְׁבִּיחוּ גְּדוֹלִים אֶת הַנְּכָסִים, הִשְׁבִּיחוּ לָאֶמְצַע. אִם אָמְרוּ רְאוּ מַה שֶּׁהִנִּיחַ לָנוּ אַבָּא, הֲרֵי אָנוּ עוֹשִׂים וְאוֹכְלִין, הִשְׁבִּיחוּ לְעַצְמָן. וְכֵן הָאִשָּׁה שֶׁהִשְׁבִּיחָה אֶת הַנְּכָסִים, הִשְׁבִּיחָה לָאֶמְצַע. אִם אָמְרָה רְאוּ מַה שֶּׁהִנִּיחַ לִי בַּעְלִי, הֲרֵי אֲנִי עוֹשָׂה וְאוֹכֶלֶת, הִשְׁבִּיחָה לְעַצְמָהּ:
If one left over sons, grown and small — If the grown ones improved the property [while it was still part of the estate, they have improved it for all (i.e., all share equally in the improvement). [This, when the property improved through the property itself, the brothers not having spent anything of their own, but having hired workers from (the proceeds of) their father's property, the property improving "of itself." But if they themselves dug and planted and spent what was theirs, then what they improved, they improved for themselves.] If they said: "See what our father left us! We shall work (the land) and eat!", they have improved it for themselves. Likewise, if a woman improved the property, she has improved it for all. If she said: "See what my husband left me! I shall work (the land) and eat!", she has improved it for herself. [The Gemara construes this as an instance of a woman's having inherited, e.g., Reuven married the daughter of Shimon, his brother, and died without children, and the daughters of Shimon, his (deceased) brother, inherit him (Reuven). It is found, then, that his (Reuven's) wife, the daughter of Shimon, his brother, inherits him with her other sisters. We might think that because of the reputation she receives as a woman who can "manage (property) and improve (it)," even if she said: "See what my husband left me, etc.!", she is willing to waive what she expended and to share the improvement with the others; we are, therefore, apprised that she has improved it for herself.]
Bartenura on Mishnah Bava Batra
English Explanation of Mishnah Bava Batra
So, too, if a woman (a improved the property, she improves it to the common benefit. If she had said, “See, what my husband left to me, lo, I will work and from that I will eat”, she improves it to her own benefit.
Mishnah three discusses sons who share an inheritance and some of the sons improve the value of the property. The issue discussed is are the sons who improved the value the only ones to profit or is the profit divided equally between all of the inheriting sons. A similar situation is discussed in which a widow improves the value of her dead husband’s property.
In the scenario mentioned in our mishnah Jacob died and left four sons, two who were older, Reuven and Shimon, and two who were younger, Levi and Judah, and Jacob owned a piece of real estate worth 1000 dollars. If Reuven and Shimon were to take this land and improve it, thereby doubling its value, each son’s portion would double. Even though Levi and Judah did not work to improve the value, since it was their inheritance as well, they receive some of the benefit. If, however, Reuven and Shimon said that they were increasing the value of their portions only, than they alone receive the increase in value.
Similarly if a widow were to increase the value of her dead husband’s estate, she would share in the increase with the sons of her husband, or the other heirs. However, if she were to state that she is improving her own lot, than she herself would receive the benefit of her work.
Note: a widow does not inherit from her husband. She is, however, entitled to receive maintenance from her husband’s estate. Maintenance payments will be based on the value of the estate: if there is a large estate she will receive better quality food, clothing and shelter. Therefore, it is in her interest to increase the value of the estate.