Jechezkiel 36:35 Mischna-Verweise: Mishnah Yevamot

If two brothers were married to two sisters who were minors and orphans, and the husband of one of them died, [the widow] is free since she is the [the yavam’s] wife’s sister. Similarly in the case of two deaf-mute [sisters]. [If the two brothers were married to two sisters one of whom was] of age and [the other] a minor, if the husband of the minor died, the minor is free since she is the [the yavam’s] wife’s sister. If the husband of the elder sister died: Rabbi Eliezer says the minor is to be instructed to make a declaration of refusal against him. Rabban Gamaliel says: If she made a declaration of refusal, then she did so; but if [she did] not, let her wait until she is of age and then she will be free since she is the [the yavam’s] wife's sister. Rabbi Joshua says: Woe to him because of his wife and woe to him because of his brother’s wife! He must allow his wife to go by [giving her] a get, and [he must let go] his brother’s wife through halitzah.