TT #693 · Parashas Ki Seitzei · Seventh Aliyah · Passuk 25:06
And it shall be that the firstborn that she bears shall succeed to the name of his dead brother, so that his name shall not be blotted out from Israel.
Torah Temimah points to Yevamot 40a.
TT lemma: יָקוּם עַל שֵׁם אָחִיו.
הַכּוֹנֵס אֶת יְבִמְתּוֹ זָכָה בְּנִכְסִים שֶׁל אָחִיו, דַּאֲמַר קְרָא יָקוּם עַל שֵׁם אָחִיו וְהֲרֵי קָם – אֲפִלּוּ יֵשׁ שָׁם אָב, וַאֲפִלּוּ גֵּרְשָׁהּ לְמָחָר.
English: One who takes his yevamah acquires the property of his brother, for Scripture says “he shall succeed to the name of his brother” — and he has succeeded — even if a father is still alive, and even if he divorces her the next day.
On the daf / in context: The acquisition of the inheritance is immediate and permanent upon the act of yibbum.
Derash on the permanence of the inheritance transfer.
The yavam acquires the deceased brother’s share immediately upon yibbum, and the acquisition stands even if a father is alive or if the marriage ends in divorce.