Gemara

42b - Suggestion: The following shows that a man does not inherit damages due to his wife, even if they were due to be paid in her lifetime!

(Beraisa): If Reuven hit a woman, making her miscarry, he pays Nezek and pain to her, and Demei Vlados (compensation for the fetus) to her husband;

If there is no husband (he died), his heirs receive (his share). If she died, her heirs receive (payment for Nezek and pain. Her husband does not inherit it!)

If she was a freed slave or a convert (and also her husband, and they died without heirs), Reuven is exempt.

Rejection (Rabah and Rav Nachman): That Beraisa discusses a divorcee.

Question: If she is a divorcee, she should share the payment for the fetus!

Answer (Rav Papa): The Torah said that the father gets it, even if she was never married to him. (It says "Ba'al ha'Ishah." We read this as if it said "Bo'el".)

49a (Mishnah): If she has no husband, his heirs receive. If she was a freed slave or a convert (and her husband was also), Reuven is exempt.

(Rabah): This is only if he hit her, and afterwards her husband died. At the time he hit her, the payment belongs to her husband. Once he dies, Reuven is exempted. If he hit her after her husband died, he must pay her.

(Rav Chisda): Payment for the fetus is not a transferable commodity! The Torah said that the husband gets it. If there is no husband, it is not paid.

Question (Beraisa): If Reuven hit a woman, making her lose her fetus, he pays Nezek and pain to her, and Demei Vlados to her husband. If the husband is dead, his heirs receive. If she died, her heirs receive.

Answer #1: Also the Beraisa discusses when he hit her in her husband's lifetime.

Answer #2: He hit her even after her husband died. The Beraisa means, whoever merits, collects (i.e. if she was hit after her husband died, she collects).

Suggestion: Tana'im argue as Rabah and Rav Chisda do.

(Beraisa #1): If a Bas Yisrael was pregnant from a convert, and Reuven hit her (in her husband's lifetime, making her miscarry), he pays her husband. If he hit her after her husband died, he is liable.

(Beraisa #2): He is exempt.

Rejection: Indeed, Rabah can hold only like Beraisa #1. However, both Tana'im could hold like Rav Chisda. Beraisa #1 holds that she gets a share of her added value due to pregnancy, like R. Shimon ben Gamliel says.

Rishonim

The Rif (21b) brings the Mishnah.

Rambam (Hilchos Chovel u'Mazik 4:2): If the husband died, his heirs receive Demei Vlados. If she was hit after her husband died, she gets Demei Vlados.

Rebuttal (Ra'avad): Even Rabah said that if he hit her after her husband died, he must pay her (49a), only if her husband was a convert. If he was a Yisrael, it goes to his heirs.

Magid Mishneh: I do not see a defense for the Rambam. The Gemara in 42b-43a is not conclusive. Perhaps the Rambam holds that "Ba'al ha'Ishah" applies only when her husband was alive when she was hit, but if he died, she gets it, like a convert's wife. This requires investigation.

Kesef Mishneh: The Rambam holds that the Halachah follows Rabah. A Beraisa teaches 'if there is no husband, his heirs receive.' This refutes Rav Chisda, who exempts Reuven when there is no husband. Rashi explained that Rav Chisda means that when there is no husband or heirs of his, but this is unlike the simple reading. Since a convert's wife receives when he died after she was hit, the same applies to any woman without a husband. This is reasonable, for one can bequeath to his sons a fine that he merited, even if he did not collect it, but he cannot bequeath what he never merited (if she was hit after he died)! The Torah says "her children" to teach that she gets Demei Vlados in this case.

Lechem Mishneh: The Stam Gemara suggested that a divorcee should share Demei Vlados. Tosfos questions this, for Rav Chisda said that Demei Vlados is not a transferable commodity! We infer that the Stam Gemara holds unlike Rav Chisda, rather, like Rabah. It seems that the Kesef Mishneh holds that the Beraisa was taught Stam, i.e. even if he hit her after her husband died. Even though this is difficult also for Rabah, we answered for Rabah that the Beraisa means that (if she was hit after her husband died,) she collects.

Question (Lechem Mishneh): The Gemara suggested that the Beraisos about a Bas Yisrael pregnant from a convert argue like Rabah and Rav Chisda. If Rav Chisda exempts Reuven whenever there is no husband, the Beraisa should have discussed even when her husband was a Yisrael!

Beis Yosef (CM 423 DH v'Li): The Beraisa taught 'if there is no husband, his heirs receive. If she died, her heirs receive. Just like in the Seifa she was hit in her lifetime, in the Reisha she was hit in his lifetime.

Rambam (3): If she was married to a convert, and he hit her in her husband's lifetime, he pays Demei Vlados to her husband. If her husband died (before he was paid), the damager is exempt.

Rosh (5:5): Rav Chisda admits that if the husband had heirs, they receive Demei Vlados. We needed a verse to teach that a man does not bequeath to his sons rights in his daughter! A Beraisa says that the sons do not get Demei Vlados; Rav Chisda says that this is when she was hit after the convert (her husband) died. He argues only with Rabah's opinion that she merits from Hefker. The Halachah follows Rav Chisda, for we say that both Tana'im can hold like him, but Rabah can be only like one Tana. Also, Rav Chisda was greater than Rabah. We find that Rabah sent a question to Rav Chisda (6b).

Rebuttal (Gra CM 423:6): The last proof is invalid. Even Rav Huna, the Rebbi of Rav Chisda, asked questions from Rabah (20b)!

Note: Tosfos (Shabbos 23b DH Gezeirah) says that Rabah and Rav Chisda were colleagues. Mo'ed Katan 28a says 'Rabah and Rav Chisda were Tzadikim...' If Rav Chisda were Rabah's Rebbi, he would be mentioned first (Otzar Meforshei ha'Talmud Bava Metzia 40a (4), citing Chidushei ha'Shas).

Hagahos Ashri: The Or Zaru'a rules like Rabah.

Poskim

Shulchan Aruch (CM 423:1): If the husband died, Reuven pays his heirs. If he hit her after her husband died, he gives Demei Vlados to her.

SMA (5): If he hit her after her husband died, it does not go to his heirs, for one does not bequeath Davar she'Lo Ba l'Olam.

Rema: Some say that he gives to his heirs.

SMA (6): It is as if the fetus belongs to the father. When he dies, his heirs are in place of him regarding rights to (be paid for) the fetus.

Shulchan Aruch (2): If she was married to a convert, and she was hit in her husband's lifetime, her husband gets Demei Vlados. If her husband died, Reuven is exempt. If he hit her after her husband died, she merits Demei Vlados.

SMA (8): This is like the Shulchan Aruch rules about a Yisrael's wife, who receives (if she was hit after her husband died).

Rema: Some say that Reuven is exempt.

SMA (9): This is like the opinion the Rema brought above, that his heirs inherit his rights, but she does not. Here, he has no heirs.