Reference for Yevamot 233:12
תא שמע הכל נאמנין להעידה חוץ מחמש נשים ואם איתא שית הויין דלמא טעמא דבת חמותה דאמרה קאכלה לגירסנא דבי נשאי לא שנא בת חמותה ולא שנא בת חמיה
also a father's wife<span class="x" onmousemove="('comment',' The stepmother of the woman in question. ');"><sup>41</sup></span> and a daughter-In-law. They<span class="x" onmousemove="('comment',' The Sages. ');"><sup>42</sup></span> said to him: A father's wife<span class="x" onmousemove="('comment',' The stepmother of the woman in question. ');"><sup>41</sup></span> is, in fact, included in the expression 'a husband's daughter',<span class="x" onmousemove="('comment',' Since a husband's daughter is ineligible as witness for a husband's wife it is obvious that the latter also, since both stand in the same relationship to one another, is equally ineligible as witness for the former. V. infra n. 6. ');"><sup>43</sup></span>