Gittin 51A

או דלמא קצובין, ואף על פי שאינן כתובים?

Or perhaps, in order to collect from liened property, it suffices that the obligation be of a fixed amount, even if it is not written?

תא שמע, דאיתמר: מי שמת והניח שתי בנות ובן, וקדמה הראשונה ונטלה עישור נכסים, ולא הספיקה שניה לגבות עד שמת הבן.

The Talmud suggests: Come and hear an answer to this question from what was stated, that the amora’im disagree about the following issue: There is a case of one who died and left two daughters and a son, and the first daughter went ahead and took 1/10th of the estate as her dowry, as sons are obligated to sustain their deceased father’s daughters until they reach majority or become betrothed and to give them part of his estate as a dowry, as daughters do not inherit when there are sons; but the second daughter did not manage to collect her tenth of the estate for her dowry before the son died. Therefore, the entire estate fell to the two daughters, who then divide it between themselves, and there is a dispute as to how they divide the estate.

אמר רבי יוחנן: שניה ויתרה. ואמר לו רבי חנינא, גדולה מזו אמרו: מוציאין לפרנסה ואין מוציאין למזונות; ואת אמרת שניה ויתרה?!

R' Yoḥanan says: The second daughter forfeited her 1/10th of the estate, and therefore she cannot demand that she should first receive 1/10th of the estate as her dowry, as did her sister, and that only afterward they divide what remains of the estate equally between themselves. And R' Ḥanina said to him: Did they not say even more than this, that if the brother sold off property belonging to his father’s estate, payment for the daughter’s dowry can be appropriated from the buyer, but payment for her sustenance cannot be appropriated from him? If the father’s estate is liened to his daughter’s dowry, so that she can collect her dowry even from a third party who bought the property from the son, she should be able to collect it from her father’s estate before it is divided up between the daughters. And you say that the second daughter forfeited her 1/10th of the estate?