If someone marries a Yevamah, the kidushin is not valid, although it is only a LAV. Is the child of this union a Mamzer, according to the Rabbonen (not Rabbi Akiva)?
Shloime Krausz, LONDON ENGLAND
The Gemara writes in Yevamos 49b that even Rebbi Akiva admits that there is no Mamzerus from a Yevamah l'Shuk, a woman who is a Yevamah who marries a man other than the brother of her deceased husband.
Actually I was referring to daf nun alef amud alef, 51a, a machloket
between Rava and Abbaye. Abbaye says a kiddushin that can not result in biah is a kiddushin and Rava says that it is not a valid kiddushin. So the question would really only apply to Rava.
Tosfos there (51a) points out that the only time there is a problem of Kidushin she'Einah Mesurah l'Biah is when the Isur comes through the Kidushin such as someone who married one of two sisters, but a woman who was Asurah notwithstanding the Kidushin, Kidushin is Tofes with Chayavei Lavin.