TT #642 · Parashas Ki Seitzei · Seventh Aliyah · Passuk 25:05
When brothers dwell together and one of them dies and has no son, the wife of the dead shall not be outside to a strange man; her husband’s brother shall come upon her and take her to himself as a wife and perform the duty of a husband’s brother for her.
Torah Temimah points to Yevamot 17b / Sifrei.
TT lemma: כִּי יֵשְׁבוּ אַחִים.
אַחִים הַמְּיֻחָדִים בְּנַחֲלָה – פְּרָט לְאַחִים מִן הָאֵם.
English: “Brothers” who are distinctive with regard to inheritance — this excludes maternal brothers.
On the daf / in context: The verse speaks only of paternal brothers, who share inheritance rights; maternal brothers are excluded from the obligation of yibbum and chalitzah.
Mi’ut excluding maternal brothers.
Only paternal brothers are subject to the laws of yibbum and chalitzah; maternal brothers are exempt.