משנה: אָמַר עֵד אֶחָד אֲנִי רְאִיתִיהָ שֶׁנִּיטְמֵאת לֹא הָיְתָה שׁוֹתָה. וְלֹא עוֹד אֶלָּא אֲפִילוּ עֶבֶד אֲפִילוּ שִׁפְחָה הֲרֵי אֵלּוּ נֶאֱמָנִין אַף לְפָסְלָהּ מִכְּתוּבָּתָהּ. חֲמוֹתָהּ וּבַת חֲמוֹתָהּ וְצָרָתָהּ וִיבִמְתָּהּ וּבַת בַּעֲלָהּ הֲרֵי אֵלּוּ נֶאֱמָנוֹת. לֹא לְפָסְלָהּ מִכְּתוּבָּתָהּ אָמְרוּ אֶלָּא שֶׁלֹּא תִשְׁתֶּה.
MISHNAH: If a single witness said “I saw her when she became impure”, she could not drink. Not only that, but even a slave or a slave-girl are believed to cause her to lose her ketubah. Her mother-in-law, the mother-in-law’s daughter, her co-wife, her sister-in-law, and her husband’s daughter are trustworthy. They said this not to make her lose her ketubah but that she could not drink.