Midrasch zu Bamidbar 27:4

(Bamidbar 27:4) "Why should the name of our father be withheld from his family because he has no son?" R. Yehudah says: It is written here "name," and elsewhere (Devarim 28:6). "Just as "name" here connotes inheritance, so, "name" there. And just as "name" here connotes seed, so, "name" there. "because he has no son": Why is this written? Is it not already written (3) "and he left no sons"? They were sage women and were expounding: But if there were a daughter of a son, we would make no claim. R. Chidka said: Shimon Hashikmoni was a colleague of mine from the disciples of R. Akiva. He said: Moses knew that daughters inherit. Where was the question? As to whether they inherit what is fit to be inherited (in Eretz Yisrael) as well as what is already in their possession. The section on inheritance was fit to be stated by Moses, but the daughters of Tzelofchad merited that it be stated through them. "Merit is effected through the meritorious and liability through the liable."

"My yavam does not desire to invest for his brother a name in Israel": R. Yehudah says: It is written here "name," and elsewhere (in connection with the daughters of Tzelafchad, Bamidbar 27:4) "name." Just as "name" there refers to seed, so, "name" here — to exclude (from chalitzah) a castrate, who, even if he wanted to perpetuate a "name" for his brother, could not.