Kiddushin 4:9-10

Kiddushin 4:9

Let’s say that a man appointed an agent to give his daughter in betrothal but then the father went and gave her in betrothal himself. In such a case, whoever gave her in betrothal first effected a valid betrothal. If it is unknown whose betrothal came first, with the result that we don’t know which is valid, then each man must give her a get. If they want, one man can give her a get and the other can marry her. Similarly, if a woman appointed an agent to betroth her but then she went and betrothed herself, the betrothal of whoever came first is effective. If it is not known who came first, each man must give her a get, or one man can give her a get and the other can marry her.

Kiddushin 4:10

If a man goes overseas with his wife and he later returns with his wife and children saying, “This is the woman who went overseas with me and these are her children,” he does not have to prove lineage for his wife and children (since his wife’s lineage would have been investigated before they married). If he says that the woman died and that these are her children, he does have to prove that they are his children from his late wife but he does not have to prove his wife’s lineage (which, as noted, was already done).