TT #702 · Parashas Ki Seitzei · Seventh Aliyah · Passuk 25:07
And if the man does not desire to take his yevamah, then his yevamah shall go up to the gate to the elders and say: “My husband’s brother refuses to establish a name for his brother in Israel; he will not perform the duty of a husband’s brother for me.”
Torah Temimah points to Sifrei / Yevamot.
TT lemma: לָקַחַת אֶת יְבִמְתּוֹ.
לָקַחַת אֶת יְבִמְתּוֹ – וְלֹא אֶת צָרָתָהּ.
English: “To take his yevamah” — and not her co-wife.
On the daf / in context: The singular language continues the exclusion of the co-wife already established in 25:5.
Mi’ut from the singular.
Chalitzah, like yibbum, is performed only with the primary yevamah, not with her co-wife when the primary woman is an ervah.