need advice....

The procedure of divorce in this case is same as it is with any other marriage. Even if they have not registered their marriage, it doesnt come in the way of filing for divorce if their marriage has been performed according to rituals provided by their religion. If any of the spouses have not claimed for annullment of marriage soon after their marriage as they were minors,then, after they have attained majority, the marriage becomes a valid marriage.

At the time of marriage the gril was minor, not both the parties.  Following sec of the Hindu marriage act may applicable on your case. Sec,13 (2) A wife may also present a petition for the dissolution of her marriage by a decree of divorce on the ground,-

(iv) that her marriage (whether consummated or not) was Solemnized before she attained the age of fifteen years and she has repudiated the marriage after attaining that age but before attaining the age of eighteen years.

for more perfect answer, more details regading date of birth of the girl date of marriage and the cause for delay in filing the petition in regard to the marriage is required.

 IT     IS   A    VALID     MARRIAGE    NOW  &    DIVORCE     SUIT    MAY    BE     FILED.