Reference for Yevamot 42:12

מאי שנא הני ומאי שנא הא הא בחד קידושין מקרב לה הני עד דאיכא תרי קידושין לא מקרב להו

in those cases<span class="x" onmousemove="('comment',' Pointed out by Raba. ');">²⁹</span> they do not become related to him until two acts of betrothal have taken place.<span class="x" onmousemove="('comment',' In the case of the wife of his father-in-law, for instance, her relationship to him is dependent on (a) his betrothal of his own wife whereby her father becomes his father-in-law, and (b) the betrothal by his father-in-law of his wife; and similarly in all the other cases pointed out by Raba. ');">³⁰</span> R. Mesharsheya of Tusaneya<span class="x" onmousemove="('comment',' [Prob. for Astunia near Pumbeditha (Obermeyer p. 229. n' 1.); cf. Keth., Sonc. ed. p. 715, n. 4. ');">³¹</span>

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