Costs may be allowed in all appealable contested matters in court to the prevailing party, to be paid by the losing party or out of the estate as justice may require; and if costs are allowed they shall be taxed by the register in probate after the notice required in ch. 814. If costs are allowed, the court shall render judgment therefor, stating in whose favor and against whom rendered and the amount, and a list of the items making the amount shall be filed with the papers in the case. Costs shall not be taxed against a guardian ad litem, except as provided in s. 814.14.