1,913. Valid and Invalid Relations
Yibum v’Chalitzah 5:8
Pursuant to the previous halachos, we see that if maamar was preceded by another maamar, a get, chalitzah or a sexual act, or if any of these actions followed the maamar, the maamar is invalid. The only exception is when the yavam gives maamar and subsequently engages in sexual intimacy with the same yevama, which is the way things are supposed to be.
Yibum v’Chalitzah 5:9
If a yavam simply engages in sexual intimacy with his yevama, or if he does so after making maamar with no other action preceding the intimacy, it is called valid relations. If one of the other brothers gave maamar to this yevama, if a get was given to her or to one of the widows, or if this yavam or one of his brothers gave maamar to one of the other widows before this couple’s intimacy, then it is considered invalid relations.