Study Guide Yevamot 37 This month's learning is sponsored by Dora Chana Haar and family for the refuah shleima of Chava Naami bat Daba Chana.  How do we rule with a baby who dies within the first month - is the baby considered viable and exempts the mother and brother from yibum or is it a case of doubt? What are the consequences for a woman who was betrothed to a man and hadn't done yibum? Is there a difference between one who was betrothed to a kohen or not? If they married immediately after the husband's death and did not wait the necessary three months and a child was born, the couple brings a hanging guilt offering? Why not go with the presumption that most women give birth after nine months and therefore require a definite sin offering? If a child is possibly a mamzer, but not definitively, can he marry a mamzeret (female mamzer)?  Different opinions are presented. What are inheritance laws for this child who is potentially the son of either the first husband or his brother? The Gemara gives various examples where there will be an argument for each side to inherit and determines what is the law in each case.