473.083.  Will binding, when — contest of will, when, procedure. — 1.  Unless any person interested in the probate of a will appears within six months after the date of the probate or rejection thereof by the probate division of the circuit court, or within six months after the first publication of notice of granting of letters on the estate of the decedent, whichever is later, and, by petition filed with the clerk of the circuit court of the county, contests the validity of a probated will, or prays to have a will probated which has been rejected by the probate division of the circuit court, then probate or rejection of the will is binding.  An heir, devisee, trustee or trust beneficiary under another purported will of the same decedent, and a person who has acquired, before or after the death of the testator, all or part of the interest of such heir or devisee by purchase, gift, devise, intestate succession, mortgage or lien, is interested in the probate of a will for purposes of this section.

  2.  Whenever it is shown or appears to and is found by the judge of the probate division that any person interested in the probate of a will is a minor or mentally incapacitated person, and that the filing of a contest may be to the interest of the minor or person, the court shall appoint a guardian ad litem for the minor or person, who shall file or join in the contest within the time fixed by subsection 1 of this section.

  3.  It is not necessary to join as parties in a will contest persons whose interests will not be affected adversely by the result thereof.  Subject to the provisions of section 472.300, persons not joined as parties in a will contest are not bound by the result thereof and have no rights in or to any consideration given for dismissal pursuant to subsection 8 of this section.

  4.  Upon filing of the petition the clerk of the circuit court shall immediately notify the probate division of the circuit court and transmit to it a copy of the petition within ten days after its filing.

  5.  Any contest of the validity of a probated will or any prayer to have probated a will which has been rejected by the judge of the probate division shall be heard before a circuit judge other than the judge of the probate division, provided, however, that with the consent of the judge of the probate division, such actions may be filed in or transferred to the probate division for hearing.  Service of summons, petition, and subsequent pleadings thereto together with all subsequent proceedings in such will contest proceedings shall be governed by the Missouri Rules of Civil Procedure and the provisions of The Civil Code of Missouri which are in effect.

  6.  In any such action the petitioner shall proceed diligently to secure and complete service of process as provided by law on all parties defendant.  If service of process is not secured and completed upon all parties defendant within ninety days after the petition is filed, the petition, on motion of any defendant duly served upon the petitioner or his attorney of record, in the absence of a showing by the petitioner of good cause for failure to secure and complete service, shall be dismissed at the cost of the petitioner.

  7.  If a timely petition is filed, it and the answer or answers thereto shall frame the issues of intestacy or testacy or which writing or writings constitute the decedent's will.  The issues shall be tried by a jury, or if no party requires a jury, by the court, and the judgment thereon shall determine the issues.  The verdict of jury or the finding and judgment of the court is final, saving to the court the right of granting a new trial and to the parties the right of appeal as in other cases.

  8.  Any such action may be voluntarily dismissed, after the period of contest has expired, by consent of all parties not in default, at the cost of the party or parties designated, at any time prior to final judgment.  Dismissal under this subsection shall not be considered a compromise of the action requiring court approval pursuant to sections 473.084 and 473.085, even though the parties have contractually agreed to an exchange of consideration for such dismissal or consent, and even though others similarly situated do not participate in such consideration.

  9.  If the action is dismissed under the provisions of subsection 6 or 8 of this section, the judge of the probate division shall proceed with the administration of the estate in accord with his previous order admitting the will to probate or rejecting a will as if the petition had never been filed with the clerk of the circuit court.