Yevamos 13:12-13

Yevamos 13:12

Let’s say that the deceased’s brother – a minor – performs yibum with the widow – also a minor. In such a case, they cannot sever their relationship until they both reach the age of majority. If the brother is a minor and the widow is an adult, they must wait for the brother to reach the age of majority. If, within 30 days, the widow says that they have still not consummated the relationship, the brother is compelled to undergo chalitzah. If she makes this claim after 30 days, they request that he undergo chalitzah (but he is not compelled because of a presumption that a couple typically consummates their relationship by this time). If he admits that they have not consummated the relationship, then even after 12 months he is compelled to undergo chalitzah.

Yevamos 13:13

Let’s say that a woman prohibits herself by making a vow not to derive benefit from her brother-in-law. If she made such a vow before her husband died, his brother is compelled to undergo chalitzah. If she made the vow after her husband died, his brother is asked to undergo chalitzah (but not compelled because her intention was to circumvent a mitzvah). If there is proof that the intention of her vow was to circumvent the mitzvah even while her husband was still alive, then the deceased’s brother is asked to undergo chalitzah (rather than compelled).