This mishnah continues the case discussed in the previous mishnah: a husband undertook to support his wife's daughter for five years, whether or not they remained married. After they were divorced his obligation remained in force, while his ex-wife married another man who took upon himself that very same obligation. In the previous mishnah we learned that both of them are obligated in her support: one provides her with actual food, and the other pays the monetary value of the food.
If the daughter marries:
The mishnah opens: "nisas" - when the daughter herself marries, it is her husband who is obligated to support her. And from now on: "ha'ba'al nosen lah mezonos, v'hen nosnin lah demei mezonos" - her husband supports her with actual food, while the two husbands, her mother's former husband and her mother's current husband, pay her the monetary value of the food.
If the husbands die:
Another issue that may arise: what is the law when both husbands have died? Here the mishnah distinguishes between their own daughters and the wife's daughter:
"benoseihen nizonos min'chasim benei chorin" - their biological daughters are supported from the estate, but only from unencumbered property, from assets that remained in the estate and were not sold.
"v'hi nizones min'chasim meshubadim" - the wife's daughter is supported even from property that has already been sold, since the obligation toward her preceded the sale, and therefore she collects even from those assets.
And the reason for this: "mipnei she'hi k'geviyas chov" - her status is like that of a creditor. Just as a creditor collects from property that was sold when the obligation toward him preceded the sale, so too this woman's daughter collects, for here there is nothing more than a monetary obligation.
Their biological daughters, by contrast, are not in the category of creditors at all. Their support is part of the marriage agreement and the stipulations of the kesubah that were set from the outset, and it does not stem from a loan or an actual debt.
And yet, even the obligation toward the wife's daughter is not a full-fledged debt. For with a real debt, if the creditor died her heirs would collect it; whereas here, if the daughter died, no one collects this support, because the undertaking to support her was given to her personally and on condition that she is alive, and not as a general debt.
The advice of the shrewd:
Because of all the complications liable to arise when a man undertakes to support his wife's daughter, the mishnah concludes: "ha'pikchim hayu kosvin: al menas she'azun es bitcha chamesh shanim kol zman she'at imi" - the wise ones would stipulate explicitly that the obligation stands only as long as the woman is married to them. If she was divorced and married another, the obligation is void, since from the start it was limited to the days of their marriage alone.
In summary: In this mishnah we learned the continuation of the laws of an undertaking to support a wife's daughter: once the daughter marries, her husband supports her with actual food and the two husbands pay her the monetary value of the food; once the husbands die, their own daughters are supported from unencumbered property alone, while she collects even from encumbered property because her claim is like the collection of a debt - even though it is not a full-fledged debt, since if she dies her heirs do not collect. And therefore the shrewd would stipulate in advance that the obligation stands only as long as the woman is with him.