If the personal property in the hands of a guardian is insufficient to pay the debts of his or her ward, including incumbrances on his or her estate, and the expense of supporting him or her and his or her family, the guardian may be authorized by the probate court to sell, or to mortgage for an amount decreed, the real estate of his or her ward or any interest therein for the purpose of paying debts. A guardian may also be authorized to sell the real estate of his or her ward or any interest in the real estate for the purpose of making a better investment or for any other proper purpose.