Related for Ketubot 6:7
הַמַּשְׁלִישׁ מָעוֹת לְבִתּוֹ, וְהִיא אוֹמֶרֶת נֶאֱמָן בַּעְלִי עָלָי, יַעֲשֶׂה הַשָּׁלִישׁ מַה שֶׁהֻשְׁלַשׁ בְּיָדוֹ, דִּבְרֵי רַבִּי מֵאִיר. רַבִּי יוֹסֵי אוֹמֵר, וְכִי אֵינָהּ אֶלָּא שָׂדֶה וְהִיא רוֹצָה לְמָכְרָהּ, הֲרֵי הִיא מְכוּרָה מֵעַכְשָׁיו. בַּמֶּה דְבָרִים אֲמוּרִים, בִּגְדוֹלָה. אֲבָל בִּקְטַנָּה, אֵין מַעֲשֵׂה קְטַנָּה כְלוּם:
If one deposits money for his daughter [If he deposits money with a third party for is daughter's needs, to buy her a field or dowry when she marries], and she says: "I trust my husband" [i.e., Give the money to him], the third party does as he was instructed. [He buys the field, and she is not heeded, for it is a mitzvah to fulfill the behest of one who has died.] These are the words of R. Meir. R. Yossi says: Is it not only a field? If she wished to sell it, she could sell it now. [That is, even if the field had already been bought and she wished to sell it, she could do so. Therefore, we heed her.] When is this so, when she is of age; but if she were a minor, the act of a minor is of no import. [R. Yossi and R. Meir differ only vis-à-vis one who is of age, during betrothal. For after she has been wed, all agree that she is heeded. And in respect to a minor, too, R. Yossi agrees that the act of a minor is of no import and she is not heeded. The halachah is in accordance with R. Meir.]