Mishnayos Yevamos Perek 13 Mishnah 4

If a minor girl refuses a man, he is permitted to marry her close relatives, such as her mother or her sister, and she is permitted to marry his close relatives, such as his father or brother, and he has not disqualified her from marrying into the priesthood, as she is not considered divorced. However, if he gave her a bill of divorce, then even though the marriage was valid according to rabbinic law and not Torah law, he is prohibited from marrying her close relatives, and she is prohibited from marrying his close relatives, and he has disqualified her from marrying into the priesthood. If he gave her a bill of divorce but afterward remarried her, and she subsequently refused him and married another man, and then she was widowed or divorced from her second husband, she is permitted to return to him. Since she left him the last time by means of refusal, the refusal cancels the bill of divorce that he gave her previously, and her status is that of a minor girl who refused her husband, who is not forbidden to her first husband after a second marriage. However, if the order was different, and if she refused him and he subsequently remarried her, and this time he gave her a bill of divorce and she married another man, and she was widowed or divorced, she is forbidden to return to him, like any divorced woman who married another man. This is the principle concerning a minor girl who refused her husband and then married several times: If the bill of divorce followed the refusal and she remarried, she is forbidden to return to him. If the refusal followed the bill of divorce, she is permitted to return to him. Since the refusal followed the bill of divorce it is clear that she was a minor and neither the marriage nor the divorce were valid by Torah law. However, when the ultimate separation is by means of a bill of divorce, there is no indication that she was a minor at the time and there is potential for confusion with an adult divorcée.