12. If, in the course of proceedings to obtain letters of administration under the provisions of section 9, section 10, or section 11, any person appears and established his claim- (a) to probate of the will of the deceased; or (b) to letters of administration as next-of-kin of the deceased, and gives such security as may be required of him by law, the Court shall grant probate of the will or letters of administration accordingly, and shall award to the Administrator General the costs of any proceedings taken by him, under those sections to be paid out of the estate as part of the testamentary or interstate expenses thereof.