The court shall appoint a suitable person to appear and act therein as the next friend of all minors, persons not ascertained and persons not in being who are or may become interested in such real estate, and the cost of the appearance and services of such next friend, including the compensation of his counsel, to be determined by the court, shall be paid as the court may order either out of the proceeds of the sale or by the petitioner. In the latter case, execution therefor may issue in the name of the next friend.