Scribal error, copying a frequent expression; it is not reasonable to follow the commentators in simply deleting the word. The sentence is a copy of the corresponding one in Sifry Deut. #289: יָצָא זֶה שֶׁכְּבָר שְׁמוֹ מָחוּי. This makes eminent sense and is the basis of the translation.
The question whether an unborn child can inherit and receive gifts is discussed in Babli Baba Batra 141b/142a, Yerushalmi Baba Batra 9:1 in a similar way. The opinion of R. Eleazar is attributed to (the slightly older) Rav Huna in the Babli.
Either this word is misspelled (some suggestions are בתינה, בתה), or a word is missing.
Reading of ms. A. Ms. L and editio princeps: במשהו “in the least amount”.
Reading of editio princeps. In ms. L: לשמונה.
Reading of ms. A. In ms. L, this sentence is identical with the preceding.
Reading of ms. A. Ms. L: ממנא.
From ms. A, missing in ms. L; necessary for the context
From ms. A; ms. L: יוסי; since clearly the reference is to R. Yasa (Assi); that reading has to be rejected.
Reading of ms. A. Ms. L: מאן.
Reading of the parallel to this paragraph in Halakhah Qiddushin 3:14. The reading here, הכא על אחות חלוצתו, is impossible since for everybody except R. Aqiba the sister of the performer of ḥalîṣah is forbidden only rabbinically and her child is acceptable to marry into the priesthood.